Air-cooled rare earth permanent magnet motor

Abstract

The utility model discloses an air-cooled rare earth permanent magnet motor, comprising a casing, two ends of which are provided with end cover assemblies, and the two end cover assemblies are respectively provided with an air induction port and an air outlet; the rotor comprises a rotor shaft, a rotor core and a permanent magnet, the rotor shaft is rotatably arranged between the two end cover assemblies in a penetrating mode, the rotor core is arranged on the periphery of the rotor shaft in a sleeving mode, the permanent magnet is arranged on the rotor core, the position, close to the permanent magnet, of the rotor core is provided with an axially-penetrating first ventilation groove, and the inner wall of the rotor core is internally concavely provided with an axially-penetrating second ventilation groove; the fan is arranged on the rotor shaft in a sleeving manner and is positioned between the air inducing opening and the rotor iron core; the stator comprises a stator iron core, and the stator iron core is arranged on the outer side of the rotor iron core in a surrounding mode. According to the air-cooled rare earth permanent magnet motor, the phenomenon of magnetic degradation of the permanent magnet caused by temperature rise of the rotor can be effectively avoided, the safety and reliability of operation are greatly improved, and meanwhile, the electric energy consumption of operation is also saved.

Description

Technical Field

[0001] The utility model relates to the technical field of permanent magnet motor heat dissipation, and more specifically to an air-cooled rare earth permanent magnet motor. Background Art

[0002] In recent years, rare earth permanent magnet motors have become increasingly popular. In high-temperature environments, permanent magnets made from high-abundance rare earth materials maintain a high magnetic energy product, making these motors compact, lightweight, and highly efficient. However, the performance of permanent magnets made from high-abundance rare earth materials degrades as rotor temperature increases, and in severe cases, irreversible demagnetization may occur. Therefore, rotor cooling is required to cool the permanent magnets and ensure safe and reliable operation of the motor.

[0003] Currently, rotors are cooled using oil and air cooling. Oil cooling typically uses a hollow rotor shaft structure, with cooling oil flowing in from one end and out from the other. However, the oil cannot cover all areas requiring cooling, such as permanent magnets, resulting in poor cooling performance and low motor reliability. Air cooling typically uses an axial fan or external blower located on one side of the rotor shaft to provide cooling air. However, the cooling air only blows across the rotor surface, resulting in poor cooling performance, low motor reliability, and increased energy consumption.

[0004] In summary, how to solve the low safety and reliability and high power consumption of existing rare earth permanent magnet motors is an urgent problem to be solved by those skilled in the art. Utility Model Content

[0005] In view of this, the purpose of the present invention is to provide an air-cooled rare earth permanent magnet motor, which can effectively avoid the magnetic degradation of the permanent magnets due to the increase in rotor temperature, greatly improve the safety and reliability of operation, and save electrical energy consumption during operation.

[0006] In order to achieve the above purpose, the present invention provides the following technical solutions:

[0007] An air-cooled rare earth permanent magnet motor, comprising:

[0008] The housing has end cover assemblies at both ends, and the two end cover assemblies are respectively provided with an air inlet and an air outlet;

[0009] The rotor comprises a rotor shaft, a rotor core, and permanent magnets, wherein the rotor shaft is rotatably disposed between the two end cover assemblies, the rotor core is sleeved on the outer circumference of the rotor shaft, the permanent magnets are disposed on the rotor core, and a first ventilation slot extending axially through the rotor core is provided adjacent to the permanent magnets, and a second ventilation slot extending axially through the rotor core is recessed in the inner wall of the rotor core;

[0010] A fan is sleeved on the rotor shaft and located between the air inlet and the rotor core;

[0011] The stator comprises a stator core, and the stator core is arranged around the outer side of the rotor core.

[0012] Preferably, the permanent magnet is embedded in the rotor core, and the first ventilation slot is located between the permanent magnet and the second ventilation slot and is arranged adjacent to both.

[0013] Preferably, the first ventilation slots and the second ventilation slots are provided in plural numbers and are arranged at equal intervals along the circumference of the rotor core.

[0014] Preferably, the radial cross-section of the first ventilation slot is waist-shaped, and / or the radial cross-section of the second ventilation slot is semicircular.

[0015] Preferably, the fan is arranged adjacent to the rotor core, and the fan includes a sleeve, a drainage ring and a plurality of blades. The sleeve is sleeved on the outer periphery of the rotor shaft, and the plurality of blades are arranged at equal intervals along the circumference of the sleeve and are all connected between the sleeve and the drainage ring.

[0016] Preferably, the distance between the outer diameter of the drainage ring and the axis center of the rotor shaft is greater than the distance between the outer diameter of the second ventilation groove and the axis center of the rotor shaft, and the distance between the drainage ring in the axial direction of the rotor shaft is greater than the distance between the fan blades in the axial direction of the rotor shaft.

[0017] Preferably, several of the fan blades are of forward-leaning blade structure.

[0018] Preferably, portions of several of the fan blades adjacent to the guide ring are provided with bosses, and all of the bosses are arranged in the same rotation direction.

[0019] Preferably, the area of ​​the air outlet is larger than the area of ​​the air inlet.

[0020] The air-cooled rare earth permanent magnet motor provided by this application has the following beneficial effects:

[0021] (1) The rotor shaft is used to drive the fan to rotate, saving power source and thus saving the electrical energy consumption of the motor operation.

[0022] (2) The first ventilation slot is arranged adjacent to the permanent magnet. Ventilation through the first ventilation slot allows air to blow over the nearby permanent magnet to fully cool the permanent magnet, thereby enhancing the cooling effect of the permanent magnet.

[0023] (3) The second ventilation slot is located on the inner wall of the rotor core. Ventilation through the second ventilation slot allows air to flow around the outer periphery of the rotor shaft to fully cool the rotor shaft, thereby enhancing the cooling effect of the rotor shaft.

[0024] (4) Both the first ventilation slot and the second ventilation slot are provided on the rotor core. Ventilation through the first ventilation slot and the second ventilation slot can fully cool the rotor core, thereby enhancing the cooling effect of the rotor core.

[0025] In summary, the air-cooled rare earth permanent magnet motor provided in this application can effectively cool the heat-generating components of the rotor to effectively avoid the magnetic degradation of the permanent magnets caused by the increase in rotor temperature, greatly improving the safety and reliability of operation, while also saving electrical energy consumption during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0027] Figure 1 This is an axonometric cross-sectional view of an air-cooled rare earth permanent magnet motor provided by the utility model;

[0028] Figure 2 This is a schematic structural diagram of the rotor core provided by the present invention;

[0029] Figure 3 A partial schematic diagram of the rotor core provided by the present invention;

[0030] Figure 4 This is a front view of the fan provided by the utility model.

[0031] Reference numerals:

[0032] 1- housing; 2- end cover assembly; 3- air inlet; 4- air outlet; 5- rotor shaft; 6- rotor core; 7- permanent magnet slot; 8- fan; 9- first ventilation slot; 10- second ventilation slot; 11- stator core; 12- stator winding;

[0033] 21-end cover; 22-bearing seat; 23-bearing cover;

[0034] 81-shaft sleeve; 82-drainage ring; 83-fan blade; 84-boss. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0036] The core of the utility model is to provide an air-cooled rare earth permanent magnet motor, which can effectively avoid the magnetic degradation of the permanent magnet due to the increase of rotor temperature, greatly improve the safety and reliability of operation, and also save the electrical energy consumption of operation.

[0037] Please refer to Figure 1 In a specific embodiment, the air-cooled rare earth permanent magnet motor provided by the present invention includes a housing 1, a rotor, a fan 8 and a stator.

[0038] End cover assemblies 2 are provided at both ends of the casing 1 , and the two end cover assemblies 2 are respectively provided with an air inlet 3 and an air outlet 4 .

[0039] The rotor includes a rotor shaft 5, a rotor core 6 and a permanent magnet. The rotor shaft 5 rotates and passes between the two end cover assemblies 2. The rotor core 6 is sleeved on the outer periphery of the rotor shaft 5. The permanent magnet is arranged on the rotor core 6. The rotor core 6 is provided with an axially penetrating first ventilation slot 9 at a position adjacent to the permanent magnet. The inner wall of the rotor core 6 is recessed with an axially penetrating second ventilation slot 10.

[0040] The fan 8 is sleeved on the rotor shaft 5 and located between the air inlet 3 and the rotor core 6 .

[0041] The stator includes a stator core 11 , which is disposed around the outside of the rotor core 6 .

[0042] It should be noted that the end cover assembly 2 generally includes an end cover 21, a bearing seat 22 and a bearing cover 23. The end cover 21 is arranged on the end of the casing 1. The bearing seat 22 is arranged on the end cover 21 for installing the bearing. The bearing is inserted into the rotor shaft 5 and supports its rotation. The bearing cover 23 is sleeved on the rotor shaft 5 extending out of the bearing and is located on the outside of the bearing, and the bearing cover 23 is sealed and connected to the bearing seat 22.

[0043] The bearing cover 23 and the bearing in one group of end cover assemblies 2 are both provided with perforations, and the two perforations are connected to form an air inlet 3. Similarly, the bearing cover 23 and the bearing in another group of end cover assemblies 2 are also provided with perforations, and the two perforations are connected to form an air outlet 4. The air inlet 3 and the air outlet 4 are both used to connect the inside and outside of the casing 1.

[0044] The rotor core 6 is a cylindrical structure, which is sleeved on the outer periphery of the rotor shaft 5. The inner wall of the rotor core 6 is concavely provided with a second ventilation groove 10, so that the second ventilation groove 10 is connected to the outer periphery of the rotor shaft 5, and the second ventilation groove 10 passes through the rotor core 6 along the axial direction of the rotor core 6. After the second ventilation groove 10 is ventilated, the air sucked into the casing 1 contacts and blows on most areas of the outer periphery of the rotor shaft 5, so as to fully cool the rotor shaft 5.

[0045] There are two ways to set up permanent magnets: one is to embed the permanent magnets in the core of the rotor core 6, and the other is to set the permanent magnets on the outer wall of the rotor core 6. Regardless of which permanent magnet setting is used, a first ventilation slot 9 is set on the core of the rotor core 6 adjacent to the permanent magnets. The first ventilation slot 9 penetrates the rotor core 6 axially. After the first ventilation slot 9 is ventilated, the air sucked into the casing 1 blows over the nearby permanent magnets to fully cool the permanent magnets. In addition, the first ventilation slot 9 and the second ventilation slot 10 also cool the rotor core 6 together to fully cool the rotor core 6.

[0046] The stator includes a stator core 11, which is arranged on the housing 1 around the circumference of the rotor core 6, with a gap between the stator core 11 and the rotor core 6. Furthermore, a stator winding 12 is wound around the stator core 11. When energized by an external power source, the stator winding 12 generates a rotating magnetic field within the stator core 11. This rotating magnetic field interacts with the permanent magnets on the rotor core 6, generating a Lorentz force that rotates the rotor core 6, thereby driving the rotor shaft 5 to rotate.

[0047] Fan 8 is built into casing 1 and sleeved onto rotor shaft 5. Rotor shaft 5 serves as the power source for rotating fan blades 83, thereby driving fan 8. This reduces the amount of power required to drive fan 8 and, consequently, the amount of energy required to operate the motor. Furthermore, fan 8 is located between the air intake and rotor core 6, drawing ambient air into casing 1 and distributing it into first and second ventilation slots 9, 10 for discharge through outlet 4.

[0048] In summary, the above-mentioned air-cooled rare earth permanent magnet motor can effectively cool the heat-generating components of the rotor, thereby effectively avoiding the magnetic degradation of the permanent magnets due to the increase in rotor temperature, greatly improving the safety and reliability of operation, and saving operating energy consumption.

[0049] On the basis of the above embodiment, the permanent magnet is embedded in the rotor core 6 , and the first ventilation slot 9 is located between the permanent magnet and the second ventilation slot 10 and is arranged adjacent to both.

[0050] Specifically, such as Figures 1 to 3As shown, the rotor core 6 is provided with first ventilation slots 9 and permanent magnet slots 7 for placing permanent magnets along the inner-outer direction. The outer diameter side of the first ventilation slots 9 is provided adjacent to the permanent magnets, and the inner diameter side is provided adjacent to the inner wall of the second ventilation slots 10. In this way, the permanent magnets are embedded in the rotor core 6, which not only facilitates the placement of the second ventilation slots 10 adjacent to the permanent magnets to fully cool them, but also facilitates the placement of the second ventilation slots 10 adjacent to the first ventilation slots 9, allowing the fan 8 to concentrate air into the two ventilation slots and reduce air volume damage.

[0051] Based on the above examples, please refer to Figure 2 and Figure 3 There are multiple first ventilation slots 9 and multiple second ventilation slots 10 , and they are arranged at equal intervals along the circumference of the rotor core 6 .

[0052] It can be understood that, first, the number of first ventilation slots 9 is increased to increase the amount of air blowing to cool the permanent magnets, and multiple first ventilation slots 9 are evenly spaced along the circumference of the rotor core 6 to uniformly cool the permanent magnets and reduce cooling dead zones, thereby enhancing the cooling effect of the permanent magnets. Second, because the rotor shaft 5 area where the rotor core 6 is mounted generates more heat than other areas of the rotor shaft 5, the number of second ventilation slots 10 is increased to increase the amount of air flowing along the outer wall of the rotor shaft 5, and multiple second ventilation slots 10 are evenly spaced along the circumference of the rotor core 6 to evenly distribute the heat to the rotor shaft 5 area that generates more heat, reduce cooling dead zones, and thus enhance the cooling effect of the rotor shaft 5. Third, because both the first ventilation slots 9 and the second ventilation slots 10 are provided on the rotor core 6, the number of both is set to multiple and evenly spaced to increase the amount of air cooling the rotor core 6 and reduce the cooling area, thereby enhancing the cooling effect of the rotor core 6.

[0053] Based on the above examples, please refer to Figure 3 The radial cross-section of the first ventilation slot 9 is waist-shaped, so as to increase the air intake volume and wind pressure of the first ventilation slot 9, thereby improving the air cooling effect of the first ventilation slot 9 on the permanent magnet.

[0054] Based on the above examples, please refer to Figure 3 The radial cross section of the second ventilation slot 10 is semicircular, so that the air passing through the second ventilation slot 10 fully contacts the outer periphery of the rotor shaft 5 , thereby enhancing the cooling effect of the second ventilation slot 10 on the rotor shaft 5 .

[0055] Based on the above examples, please refer to Figure 1 and Figure 4 The fan 8 is arranged adjacent to the rotor core 6. The fan 8 includes a sleeve 81, a drainage ring 82 and a plurality of blades 83. The sleeve 81 is sleeved on the outer periphery of the rotor shaft 5. The plurality of blades 83 are arranged at equal intervals along the circumference of the sleeve 81 and are all connected between the sleeve 81 and the drainage ring 82.

[0056] It is understood that fan 8 is positioned adjacent to rotor core 6, such that fan 8 is positioned adjacent to first ventilation slot 9 and second ventilation slot 10, thereby improving ventilation at the air inlet and outlet ends of the two ventilation slots and ensuring smooth air flow within the two ventilation slots. Furthermore, a guide ring 82 is positioned around and outside of several blades 83, serving to guide air, effectively directing the air disturbed by fan 8 into first ventilation slot 9 and second ventilation slot 10, thereby enhancing the cooling effect of the rotor.

[0057] Furthermore, the distance between the outer diameter of the guide ring 82 and the axis of the rotor shaft 5 is greater than the distance between the outer diameter of the second ventilation slot 10 and the axis of the rotor shaft 5, and the distance between the guide ring 82 and the rotor shaft 5 in the axial direction is greater than the distance between the blades 83 and the rotor shaft 5 in the axial direction. Therefore, the guide ring 82 is arranged in this manner so that all the blades 83 are located within the guide ring 82, which facilitates the centralized air supply to the first ventilation slot 9 and the second ventilation slot 10, greatly reducing air volume loss, thereby further improving the cooling effect of the rotor.

[0058] On the basis of the above embodiment, the plurality of blades 83 are all in a forward-leaning blade structure, which can enable the fan 8 to form a greater wind pressure, so as to be able to inhale more external air, thereby improving the cooling effect of the rotor.

[0059] Based on the above examples, please refer to Figure 4 , portions of the plurality of blades 83 adjacent to the guide ring 82 are each provided with a boss 84 , and all bosses 84 are arranged in the same rotation direction.

[0060] Specifically, the portion of blade 83 adjacent to guide ring 82 is provided with a boss 84, giving blade 83 a stepped structure. Compared to conventional blades 83, this increases the area of ​​blade 83, thereby increasing the amount of air drawn in and out by fan 8, thereby improving the cooling effect of the rotor. It should be noted that the bosses 84 on all blades 83 face the same rotational direction to ensure that fan 8 generates stable airflow during rotation.

[0061] Based on the above embodiment, the area of ​​the air outlet 4 is larger than that of the air inlet 3. It is understood that as the outside air passes through the first ventilation slots 9 and the second ventilation slots 10, the air's temperature rises through heat exchange with the various heat-generating components of the rotor, turning it into hot air. The hot air expands in volume compared to the outside air. Therefore, the area of ​​the air outlet 4 is larger than that of the air inlet 3, which helps reduce wind resistance at the air outlet 4, thereby improving air flow efficiency and, consequently, rotor cooling efficiency.

[0062] It should be noted that, in this specification, relational terms such as first and second are merely used to distinguish one entity from other entities, but do not necessarily require or imply any actual relationship or order between these entities.

[0063] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0064] The above describes in detail the air-cooled rare earth permanent magnet motor provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above examples is only intended to help understand the method and core concept of the present invention. It should be noted that those skilled in the art may make various improvements and modifications to the present invention without departing from the principles of the present invention, and such improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. An air-cooled rare earth permanent magnet motor, characterized in that: include: A casing (1) is provided with end cover assemblies (2) at both ends, and the two end cover assemblies (2) are respectively provided with an air inlet (3) and an air outlet (4); A rotor comprising a rotor shaft (5), a rotor core (6) and a permanent magnet, wherein the rotor shaft (5) is rotatably arranged between the two end cover assemblies (2), the rotor core (6) is sleeved on the outer periphery of the rotor shaft (5), the permanent magnet is arranged on the rotor core (6), and a first ventilation slot (9) extending axially through the rotor core (6) is provided at a position adjacent to the permanent magnet, and a second ventilation slot (10) extending axially through the rotor core (6) is provided in a recessed manner on an inner wall of the rotor core (6); A fan (8) is sleeved on the rotor shaft (5) and located between the air inlet (3) and the rotor core (6); The stator comprises a stator iron core (11), wherein the stator iron core (11) is arranged around the outside of the rotor iron core (6).

2. The air-cooled rare earth permanent magnet motor according to claim 1, characterized in that: The permanent magnet is embedded in the rotor core (6), and the first ventilation slot (9) is located between the permanent magnet and the second ventilation slot (10) and is arranged adjacent to both.

3. The air-cooled rare earth permanent magnet motor according to claim 1, characterized in that: The first ventilation slots (9) and the second ventilation slots (10) are both provided in plurality and are arranged at equal intervals along the circumference of the rotor core (6).

4. The air-cooled rare earth permanent magnet motor according to claim 1, characterized in that: The radial cross-section of the first ventilation slot (9) is waist-shaped, and / or the radial cross-section of the second ventilation slot (10) is semicircular.

5. The air-cooled rare earth permanent magnet motor according to claim 1, characterized in that: The fan (8) is arranged adjacent to the rotor core (6), and comprises a shaft sleeve (81), a flow guide ring (82), and a plurality of blades (83). The shaft sleeve (81) is sleeved on the outer periphery of the rotor shaft (5), and the plurality of blades (83) are arranged at equal intervals along the circumference of the shaft sleeve (81) and are all connected between the shaft sleeve (81) and the flow guide ring (82).

6. The air-cooled rare earth permanent magnet motor according to claim 5, characterized in that: The distance between the outer diameter of the guide ring (82) and the axis center of the rotor shaft (5) is greater than the distance between the outer diameter of the second ventilation slot (10) and the axis center of the rotor shaft (5), and the distance between the guide ring (82) in the axial direction of the rotor shaft (5) is greater than the distance between the fan blades (83) in the axial direction of the rotor shaft (5).

7. The air-cooled rare earth permanent magnet motor according to claim 5, characterized in that: The plurality of fan blades (83) are all in a forward-leaf structure.

8. The air-cooled rare earth permanent magnet motor according to claim 5, characterized in that: Portions of the plurality of blades (83) adjacent to the guide ring (82) are each provided with a boss (84), and all of the bosses (84) are arranged in the same rotation direction.

9. The air-cooled rare earth permanent magnet motor according to any one of claims 1 to 8, characterized in that: The area of ​​the air outlet (4) is larger than the area of ​​the air inlet (3).

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