Rotor of built-in permanent magnet motor, built-in permanent magnet motor and electric equipment

Abstract

The utility model relates to a rotor of a built-in permanent magnet motor, the built-in permanent magnet motor and electric equipment, in the rotor of the built-in permanent magnet motor, a rotor core is sleeved outside a shaft body, a plurality of tangential permanent magnets are distributed in the rotor core in the circumferential direction of the shaft body, the directions of magnetic induction lines of two adjacent tangential permanent magnets are opposite, and the tangential permanent magnets are arranged in the rotor core. Each radial permanent magnet is correspondingly arranged between two adjacent tangential permanent magnets; wherein the rotor core is provided with a plurality of reinforcing ribs, each reinforcing rib is correspondingly arranged between the adjacent tangential permanent magnet and radial permanent magnet, the magnetic induction line direction of the radial permanent magnet located between the first magnetic pair is far away from the axis of the shaft body, and the magnetic induction line direction of the radial permanent magnet located between the second magnetic pair points to the axis of the shaft body. According to the invention, the breath flux density of the motor can be improved, and the overall performance of the motor is improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of motors, and in particular to a rotor of an interior permanent magnet motor, an interior permanent magnet motor, and an electric device. Background Art

[0002] Internal permanent magnet motors are widely used in various electric devices due to their high efficiency and low noise. Internal permanent magnet motors include a stator and a rotor. The rotor is arranged inside the stator, and there is a gap between the inner wall of the stator and the outer wall of the rotor. The rotor includes a rotor core and a permanent magnet. The magnetic field intensity excited by the permanent magnet in the above gap is called air gap flux density. The air gap flux density is one of the important bases for measuring motor performance. How to manufacture a motor with a larger air gap flux density at a lower cost is the current research focus.

[0003] In the related technology, the air gap magnetic flux density can be improved by making full use of the space in the rotor core. A plurality of tangential permanent magnets (the magnetic field direction is the rotor tangential) are arranged at intervals in the rotor. A radial permanent magnet (the magnetic field direction is the rotor radial) is arranged in the space between two adjacent tangential permanent magnets, so that part of the magnetic flux lines of the radial permanent magnet pass through the above-mentioned gap, thereby achieving the improvement of the air gap magnetic flux density.

[0004] However, in the above structure, two radial permanent magnets are arranged between two adjacent tangential permanent magnets, and the two radial permanent magnets are separated by reinforcing ribs. For any radial permanent magnet, the magnetic flux lines between its two poles can directly form a closed loop through the reinforcing ribs without passing through the above gap, that is, there is obvious magnetic leakage in the radial permanent magnet, resulting in a small air gap magnetic density. Utility Model Content

[0005] The embodiments of the present disclosure provide a rotor of an internal permanent magnet motor, an internal permanent magnet motor, and an electric device, which can solve the technical problems existing in the related art. The technical solutions are as follows:

[0006] In a first aspect, an embodiment of the present disclosure provides a rotor of an interior permanent magnet motor, the rotor comprising a shaft, a rotor core, a plurality of tangential permanent magnets and a plurality of radial permanent magnets;

[0007] The rotor core is sleeved outside the shaft body;

[0008] The plurality of tangential permanent magnets are circumferentially distributed around the shaft body inside the rotor core, and the directions of the magnetic flux lines of two adjacent tangential permanent magnets are opposite;

[0009] Each of the radial permanent magnets is correspondingly arranged between two adjacent tangential permanent magnets;

[0010] In which, the rotor core has a plurality of reinforcing ribs, each of which is correspondingly arranged between adjacent tangential permanent magnets and radial permanent magnets, and two adjacent tangential permanent magnets with opposite magnetic flux lines form a first magnetic pair, and two adjacent tangential permanent magnets with opposite magnetic flux lines form a second magnetic pair; the direction of the magnetic flux lines of the radial permanent magnets located between the first magnetic pair is away from the axis of the shaft, and the direction of the magnetic flux lines of the radial permanent magnets located between the second magnetic pair points to the axis of the shaft, and the direction of the magnetic flux lines is the internal magnetic flux line direction of the permanent magnet.

[0011] In a possible implementation, the rotor core has a plurality of first slot bodies and a plurality of second slot bodies inside;

[0012] The plurality of first slots are distributed circumferentially around the shaft, and the first slots are used to accommodate the tangential permanent magnets;

[0013] Each of the second slot bodies is correspondingly arranged between two adjacent first slot bodies, and the second slot body is used to accommodate the radial permanent magnet.

[0014] In a possible implementation, the rotor core further has a connecting rib, which is located on a side of an end surface of the first slot body away from the shaft body, and two ends of the connecting rib are respectively connected to two opposite wall surfaces of the first slot body in a tangential direction.

[0015] In a possible implementation manner, the thickness of the connecting rib is smaller than the thickness of the reinforcing rib.

[0016] In a possible implementation manner, there is a gap between the tangential permanent magnet and a wall surface of the first slot body close to the shaft body.

[0017] In a possible implementation, the rotor further includes a magnetic blocking member, which is located in the gap, and two ends of which are respectively against the tangential permanent magnet and a wall surface of the first slot body close to the shaft body.

[0018] In a possible implementation, the radial distance from the first end face of the tangential permanent magnet to the shaft body is a first value, the radial distance from the first end face of the radial permanent magnet to the shaft body is a second value, the radial distance from the second end face of the radial permanent magnet to the shaft body is a third value, the difference between the third value and the first value is a first difference, the difference between the first value and the second value is a second difference, and the first difference is not less than the second difference;

[0019] Among them, the first end face of the tangential permanent magnet is the end face of the tangential permanent magnet close to the shaft body, the first end face of the radial permanent magnet is the end face of the radial permanent magnet close to the shaft body, and the second end face of the radial permanent magnet is the end face of the radial permanent magnet away from the shaft body.

[0020] In a possible implementation, the shaft body and the rotor core are connected via a spline.

[0021] In a second aspect, an embodiment of the present disclosure provides an internal permanent magnet motor, wherein the internal permanent magnet motor comprises the rotor in the first aspect and possible implementations thereof.

[0022] In a third aspect, an embodiment of the present disclosure provides an electric device, which includes the rotor in the first aspect and possible implementations thereof or the built-in permanent magnet motor in the second aspect and possible implementations thereof.

[0023] The technical solution provided by the embodiments of the present disclosure includes at least the following beneficial effects:

[0024] An embodiment of the present disclosure provides a rotor of an interior permanent magnet motor, the rotor comprising a shaft, a rotor core, a plurality of tangential permanent magnets, and a plurality of radial permanent magnets.

[0025] The rotor core is sleeved outside the shaft. A plurality of tangential permanent magnets are circumferentially distributed inside the rotor core around the shaft, and the directions of the magnetic flux lines of two adjacent tangential permanent magnets are opposite. Each radial permanent magnet is correspondingly arranged between two adjacent tangential permanent magnets. In addition, the rotor core has a plurality of reinforcing ribs, each reinforcing rib is correspondingly arranged between adjacent tangential permanent magnets and radial permanent magnets, two adjacent tangential permanent magnets with opposite directions of magnetic flux lines form a first magnetic pair, and two adjacent tangential permanent magnets with opposite directions of magnetic flux lines form a second magnetic pair; the direction of the magnetic flux lines of the radial permanent magnets located between the first magnetic pair is away from the axis of the shaft, and the direction of the magnetic flux lines of the radial permanent magnets located between the second magnetic pair points to the axis of the shaft, and the direction of the magnetic flux lines is the direction of the internal magnetic flux lines of the permanent magnets.

[0026] In this way, a tangential permanent magnet is arranged between each two adjacent radial permanent magnets, and reinforcing ribs are provided on both sides of each radial permanent magnet. For any radial permanent magnet whose magnetic flux lines point to the axis of the shaft body, since the distance between its N (north) pole and the S (south) pole of the adjacent tangential permanent magnet is closer than the distance between its N pole and the S pole of the radial permanent magnet, the magnetic resistance is smaller, and when the magnetic flux lines drawn from the N pole pass through the reinforcing ribs, most of the magnetic flux lines will pass through the adjacent tangential permanent magnets and the adjacent radial permanent magnets in sequence and then return to the S pole of the radial permanent magnet, rather than directly forming a closed loop from the N pole to the S pole of the radial permanent magnet, that is, the leakage magnetic flux of the radial permanent magnet is reduced, and the air gap magnetic density can be improved.

[0027] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] Figure 1 is a schematic structural diagram of a rotor of an internal permanent magnet motor shown in an embodiment of the present disclosure;

[0030] Figure 2 is a schematic structural diagram of a rotor core shown in an embodiment of the present disclosure;

[0031] Figure 3 is a schematic structural diagram of a rotor of an internal permanent magnet motor shown in an embodiment of the present disclosure;

[0032] Figure 4 is a schematic structural diagram of a rotor of an internal permanent magnet motor shown in an embodiment of the present disclosure;

[0033] Figure 5 is a schematic diagram of the distribution of magnetic flux lines inside a built-in permanent magnet motor shown in an embodiment of the present disclosure;

[0034] Figure 6 is a schematic diagram of the distribution of magnetic flux lines inside a built-in permanent magnet motor shown in an embodiment of the present disclosure;

[0035] Figure 7 It is a schematic structural diagram of a built-in permanent magnet motor shown in an embodiment of the present disclosure.

[0036] Legend

[0037] 1. rotor; 100. first magnetic pair; 200. second magnetic pair; 300. gap;

[0038] 11. Shaft; 12. Rotor core; 13. Tangential permanent magnet; 14. Radial permanent magnet; 15. Magnetic resistance;

[0039] 120, spline receiving groove; 121, first groove body; 122, second groove body; 123, reinforcing rib; 124, connecting rib;

[0040] 131. a first tangential permanent magnet;

[0041] 13a, a first end surface tangential to the permanent magnet;

[0042] 141. a first radial permanent magnet; 142. a second radial permanent magnet;

[0043] 14a, a first end surface of the radial permanent magnet; 14b, a second end surface of the radial permanent magnet;

[0044] 2. Stator;

[0045] 21. stator core; 22. coil winding;

[0046] 211. The third tank. DETAILED DESCRIPTION

[0047] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0048] Unless otherwise defined, the technical terms or scientific terms used herein shall have the usual meanings understood by persons with ordinary skills in the field to which the present disclosure belongs. The words "first", "second", "third" and similar words used in the patent disclosure specification and claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not indicate a quantity limitation, but indicate the existence of at least one. Words such as "include" or "comprise" and similar words mean that the elements or objects appearing before "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalents, and do not exclude other elements or objects. Words such as "connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0049] The built-in permanent magnet motor uses an iron core equipped with permanent magnets as the rotor, and does not require electromagnetic windings for excitation, so it has higher efficiency and lower energy consumption. At the same time, the rotor in the built-in permanent magnet motor has a smaller volume and lighter weight than the rotor in the traditional induction motor, so the noise is lower in the working state. Based on these characteristics, the built-in permanent magnet motor is widely used in various electric devices. The built-in permanent magnet motor includes a stator and a rotor. The rotor is arranged inside the stator, and there is a gap between the inner wall of the stator and the outer wall of the rotor. The rotor includes a rotor core and a permanent magnet. The permanent magnet is assembled inside the rotor core. The magnetic field intensity excited by the permanent magnet in the gap between the stator and the rotor is called the air gap flux density. At present, the research focus in the industry is on how to manufacture a motor with a larger air gap flux density at a lower cost.

[0050] There are multiple tangential permanent magnets distributed inside the rotor core along the circumferential direction of the shaft (the direction of the internal magnetic flux lines of the permanent magnets points to the tangential direction of the rotor). Under the influence of magnetic force, multiple tangential permanent magnets need to be arranged at intervals, that is, a certain space needs to be left between two adjacent tangential permanent magnets inside the rotor core. In practice, when manufacturing the rotor of the internal permanent magnet motor, the air gap flux density can be improved by making full use of the space inside the rotor core. Figure 1 ( Figure 1 , which is a structural diagram of the rotor of the internal permanent magnet motor corresponding to the related technology, is provided with a radial permanent magnet between two adjacent tangential permanent magnets (the direction of the internal magnetic flux lines of the permanent magnets points to the radial direction of the rotor), and part of the magnetic flux lines excited by the radial permanent magnets will pass through the gap between the stator and the rotor, thereby increasing the air gap magnetic flux density. However, if Figure 1 As shown, since two radial permanent magnets are arranged between two adjacent tangential permanent magnets, and the two radial permanent magnets are separated by reinforcing ribs, the magnetic flux lines between the two poles of the radial permanent magnets can directly form a closed loop through the reinforcing ribs without passing through the gap between the stator and the rotor, that is, there is obvious magnetic leakage in the radial permanent magnets, and the cost increased by arranging radial permanent magnets fails to maximize the improvement of the air gap magnetic density.

[0051] The embodiment of the present disclosure provides a rotor 1 of an interior permanent magnet motor. The rotor 1 includes a shaft 11 , a rotor core 12 , a plurality of tangential permanent magnets 13 , and a plurality of radial permanent magnets 14 .

[0052] The rotor core 12 is sleeved outside the shaft 11. A plurality of tangential permanent magnets 13 are circumferentially distributed inside the rotor core 12 around the shaft 11, and the directions of the magnetic flux lines of two adjacent tangential permanent magnets 13 are opposite. Each radial permanent magnet 14 is correspondingly arranged between two adjacent tangential permanent magnets 13. In addition, the rotor core 12 has a plurality of reinforcing ribs 123, each reinforcing rib 123 is correspondingly arranged between adjacent tangential permanent magnets 13 and radial permanent magnets 14, two adjacent tangential permanent magnets 13 with opposite directions of magnetic flux lines form a first magnetic pair 100, and two adjacent tangential permanent magnets 13 with opposite directions of magnetic flux lines form a second magnetic pair 200; the direction of the magnetic flux lines of the radial permanent magnets 14 located between the first magnetic pair 100 is away from the axis of the shaft 11, and the direction of the magnetic flux lines of the radial permanent magnets 14 located between the second magnetic pair 200 points to the axis of the shaft 11, and the direction of the magnetic flux lines is the direction of the internal magnetic flux lines of the permanent magnets. In this way, a tangential permanent magnet 13 is arranged between each two adjacent radial permanent magnets 14, and reinforcing ribs 123 are provided on both sides of each radial permanent magnet 14. For any radial permanent magnet 14 whose magnetic flux lines are directed to the axis of the shaft body 11, since the distance between its N pole and the S pole of the adjacent tangential permanent magnet 13 is closer than the distance between its N pole and the S pole of the radial permanent magnet 14, the magnetic resistance is smaller, and when the magnetic flux lines drawn from the N pole pass through the reinforcing ribs 123, most of the magnetic flux lines will pass through the adjacent tangential permanent magnet 13 and the adjacent radial permanent magnet 14 in sequence and then return to the S pole of the radial permanent magnet 14, rather than directly forming a closed loop from the N pole to the S pole of the radial permanent magnet 14, that is, the leakage magnetic flux of the radial permanent magnet 14 is reduced, and the air gap magnetic density can be improved.

[0053] Next, the various components of the rotor 1 of the interior permanent magnet motor are introduced respectively:

[0054] 1. Axis 11

[0055] The shaft 11 is a component in the rotor 1 of the interior permanent magnet motor that is used to connect with the rotor core 12 and the rotating components.

[0056] In practice, one end of the shaft 11 is connected to the rotor core 12, and the other end is connected to the rotating component. The rotor core 12 rotates under the action of the stator to drive the shaft 11 to rotate, and the shaft 11 transmits the driving force to the rotating component to drive the rotating component to rotate.

[0057] like Figure 2 As shown, the shaft body 11 is located in the inner ring of the rotor core 12 and is connected to the rotor core 12 .

[0058] In one example, the shaft 11 and the rotor core 12 are connected via a spline.

[0059] like Figure 2As shown, the shaft body 11 has a cylindrical structure, and the outer ring of the shaft body 11 has a plurality of spline mounting grooves (not shown), and the plurality of spline mounting grooves are circumferentially distributed around the shaft body 11. The rotor core 12 has a cylindrical structure, and the inner wall of the rotor core 12 has a plurality of spline receiving grooves 120, and the plurality of spline receiving grooves 120 are circumferentially distributed around the shaft body 11, and each spline receiving groove 120 corresponds to a spline mounting groove. Two adjacent spline receiving grooves 120 are transitionally connected by the inner wall of the rotor core 12.

[0060] In implementation, the spline can be first installed in the spline installation groove to achieve a fixed connection between the spline and the shaft body 11, and then the connection between the shaft body 11 and the rotor core can be achieved through the cooperation between the spline and the spline receiving groove 120.

[0061] Exemplarily, the connection between the spline and the spline mounting groove of the shaft body 11 can be a snap connection, which is not limited in the embodiments of the present disclosure.

[0062] Optionally, the spline receiving groove 120 may be in an arc shape.

[0063] In this way, stress concentration on the spline receiving groove 120 and the spline wall surface can be reduced, and the connection strength between the shaft body 11 and the rotor core 12 can be improved.

[0064] In one example, the shaft body 11 and the rotor core 12 are connected by interference fit.

[0065] In this way, the connection stability between the shaft body 11 and the rotor core 12 can be improved.

[0066] The material of the shaft body 11 can be selected from high-quality alloy steel, such as 45 steel, 40Cr, 35CrMo, etc. The embodiment of the present disclosure does not limit the specific material of the shaft body 11.

[0067] In one possible implementation, the shaft 11 can be made of a magnetic conductive material, for example, a ferromagnetic material, etc. This can enhance the magnetic field strength between the rotor 1 and the stator, that is, increase the air gap flux density, thereby improving the overall performance of the built-in permanent magnet motor.

[0068] The shaft body 11 can be formed by a cutting process, and the embodiment of the present disclosure does not limit the processing method of the shaft body 11.

[0069] In an example, the shaft body 11 may include a shaft body and a shaft yoke. The shaft body is located in the inner ring of the shaft yoke and is connected to the shaft jaw, and the shaft jaw is used to be connected to the rotor core 12.

[0070] The shaft body can be made of any material with high rigidity, for example, a metal material with high rigidity, etc., and the shaft yoke is made of a magnetic conductive material, for example, a silicon steel material or a ferromagnetic material, etc. In this way, the overall strength of the shaft body 11 can be improved, and the magnetic field strength between the motor rotor 1 and the motor stator can be enhanced, thereby improving the overall performance of the built-in permanent magnet motor.

[0071] 2. Rotor core 12

[0072] The rotor core 12 is a component of the rotor 1 for accommodating permanent magnets.

[0073] like Figure 3 As shown, the rotor core 12 has a cylindrical structure, and is coaxially arranged with the shaft body 11. The rotor core 12 is sleeved on the outer ring of the shaft body 11 and connected to the shaft body 11. The rotor core 12 is used to accommodate a plurality of tangential permanent magnets 13 and a plurality of radial permanent magnets 14.

[0074] The rotor core 12 may be made of a magnetic conductive material with good magnetic conductivity for enhancing the magnetic field strength and thus improving the air gap flux density. For example, it may be made of ferromagnetic material, silicon steel material, etc., which is not limited in the embodiments of the present disclosure.

[0075] In some possible embodiments, the rotor core 12 has a plurality of first slot bodies 121 and a plurality of second slot bodies 122 inside.

[0076] like Figure 3 As shown, a plurality of first slots 121 are circumferentially distributed around the shaft body 11, the first slots 121 are used to accommodate the tangential permanent magnets 13, and the first slots 121 extend along the axis direction of the shaft body 11. Each second slot 122 is correspondingly arranged between two adjacent first slots 121, the second slots 122 are used to accommodate the radial permanent magnets 14, and the second slots 122 extend along the axis direction of the shaft body 11.

[0077] In one example, the first slot body 121 and the second slot body 122 can be formed by a stamping process.

[0078] The first groove body 121 and the second groove body 122 may be formed in the same processing process, or may be formed separately in multiple processing processes, which is not limited in the embodiments of the present disclosure.

[0079] In one example, the rotor core 12 having the first slot body 121 and the second slot body 122 can be formed by a casting process.

[0080] In this way, the processing cost of the first trough body 121 and the second trough body 122 can be reduced.

[0081] The number and size of the plurality of first slot bodies 121 and the plurality of second slot bodies 122 can be set according to needs and in comprehensive consideration of the structure of the motor stator, and the embodiments of the present disclosure are not limited to this.

[0082] For example, reference Figure 3 The rotor core 12 has 10 first slots 121 and 10 second slots 122 inside. Both the first slots 121 and the second slots 122 are rectangular grooves. The top of the first slot 121 points to the bottom of the slot in parallel with the radial direction of the shaft 11. The top of the second slot 122 points to the bottom of the slot in parallel with the radial direction of the shaft 11. The angle between the top of two adjacent first slots 121 and the bottom of the slot is 36°. Correspondingly, the angle between the top of two adjacent second slots 122 and the bottom of the slot is also 36°.

[0083] Optionally, the sizes of the plurality of first slot bodies 121 may all be the same, and the sizes of the plurality of second slot bodies 122 may all be the same.

[0084] In this way, after the tangential permanent magnet 13 is assembled with the first slot body 121 and the radial permanent magnet 14 is assembled with the second slot body 122 , the connection stability between the permanent magnet and the rotor core 12 can be improved.

[0085] In some possible embodiments, the rotor core 12 may include a rotor body and a rotor yoke. The rotor yoke has a cylindrical structure. The rotor yoke is located on the outer ring of the shaft body 11 and is connected to the shaft body 11. The rotor body is located on the outer ring of the rotor yoke and is connected to the rotor body. The rotor body and the rotor yoke may be integrally formed, thereby improving the overall strength of the rotor core 12.

[0086] In some possible embodiments, the rotor core 12 further has connecting ribs 124 .

[0087] like Figure 3 As shown, the connecting rib 124 is located on the end surface of the first slot body 121 away from the shaft body 11, and the two ends of the connecting rib 124 are respectively connected to two opposite wall surfaces of the first slot body 121 in the tangential direction.

[0088] In this way, the tangential permanent magnet 13 is assembled to the first slot body 121 , and the connecting rib 124 can be used to support the end of the tangential permanent magnet 13 away from the shaft body 11 , thereby improving the connection strength between the tangential permanent magnet 13 and the rotor core 12 .

[0089] In one example, the connection ribs 124 and the rotor core 12 may be an integrally formed component.

[0090] When the first slot body 121 is formed by stamping, cutting or casting, the connecting rib 124 and the rotor core 12 can be an integrally formed component, that is, when the first slot body 121 is formed, a thin-walled structure is left on the outer ring of the rotor core 12 to form the connecting rib 124, which can reduce the processing cost.

[0091] In one example, the connection ribs 124 and the rotor core 12 may be parts formed in separate steps.

[0092] In implementation, a plurality of first slot bodies 121 can be firstly formed on the outer wall of the rotor core 12 having a cylindrical structure along the axial direction of the shaft body 11, and then, the connecting rib 124 can be arranged on the side of the first slot body 121 away from the shaft body 11, and the two ends of the connecting rib 124 can be respectively connected to the two groove eaves of the first slot body 121, or, the two ends of the connecting rib 124 can be respectively connected to the two opposite wall surfaces in the first slot body 121.

[0093] The connection between the connecting rib 124 and the first slot body 121 may be by welding or bonding, which is not limited in the embodiment of the present disclosure.

[0094] Optionally, the thickness of the connecting rib 124 may be smaller than the thickness of the reinforcing rib 123 .

[0095] For example, reference Figure 3 The connecting rib 124 has an n-shaped structure, and the thickness of the connecting rib 124 is within a first preset range, and the value of the first preset range can be [0.2 mm, 0.5 mm].

[0096] In this way, the thickness of the connecting rib 124 is small and the magnetic resistance is large. When the tangential permanent magnet 13 is arranged in the first slot body 121, the N pole and the S pole of the tangential permanent magnet 13 are respectively attached to the two opposite walls in the first slot body 121. Since the magnetic resistance of the connecting rib 124 is large, only a small part of the magnetic flux lines drawn from the N pole of the tangential permanent magnet 13 directly form a closed loop with the S pole through the connecting rib 124. That is, the thickness of the connecting rib 124 is set within the first preset range, which can reduce the leakage magnetic flux of the tangential permanent magnet 13 and improve the air gap magnetic density.

[0097] 3. Tangential permanent magnet 13 and radial permanent magnet 14

[0098] The tangential permanent magnets 13 and the radial permanent magnets 14 are components in the rotor 1 for exciting a magnetic field at the outer ring of the electronic core.

[0099] like Figure 2As shown, multiple tangential permanent magnets 13 are located inside the rotor core 12 and distributed circumferentially around the shaft 11 , multiple radial permanent magnets 14 are located inside the rotor core 12 , and each radial permanent magnet 14 is correspondingly arranged between two adjacent tangential permanent magnets 13 .

[0100] Among them, the directions of the magnetic flux lines of two adjacent tangential permanent magnets 13 are opposite, the direction of the magnetic flux lines of the radial permanent magnets 14 located between the first magnetic pair 100 is away from the axis of the shaft body 11, and the direction of the magnetic flux lines of the radial permanent magnets 14 located between the second magnetic pair 200 points to the axis of the shaft body 11. The first magnetic pair 100 includes two adjacent tangential permanent magnets 13 with opposite magnetic flux lines, and the second magnetic pair 200 includes two adjacent tangential permanent magnets 13 with opposite magnetic flux lines. The direction of the magnetic flux lines is the internal magnetic flux line direction of the permanent magnet.

[0101] In a possible embodiment, the rotor core 12 has a plurality of first slot bodies 121 and a plurality of second slot bodies 122 inside, the plurality of first slot bodies 121 are distributed circumferentially around the shaft body 11 , and each second slot body 122 is correspondingly disposed between two adjacent first slot bodies 121 .

[0102] The shape and size of the tangential permanent magnet 13 match those of the first slot body 121, and the shape and size of the radial permanent magnet 14 match those of the second slot body 122. Multiple tangential permanent magnets 13 are correspondingly arranged in different first slot bodies 121 and connected to the rotor core 12. The magnetic flux lines of two adjacent tangential permanent magnets 13 are in opposite directions, that is, for any tangential permanent magnet 13, when its magnetic flux lines point to the counterclockwise direction of the tangential direction of the rotor 1, the magnetic flux lines of two adjacent tangential permanent magnets 13 of the tangential permanent magnet 13 point to the clockwise direction of the tangential direction of the rotor 1. Multiple radial permanent magnets 14 are correspondingly arranged in different second slot bodies 122 and connected to the rotor core 12.

[0103] In implementation, Figure 2 As shown, the rotor 1 includes multi-pole magnets, each pole magnet includes two tangential permanent magnets 13 and a radial permanent magnet 14 located between the two tangential permanent magnets 13 (that is, each pole magnet includes three permanent magnets), and the adjacent two pole magnets have two radial permanent magnets 14, and the adjacent two pole magnets share the tangential permanent magnet located between the two radial permanent magnets 14. In this way, there are a total of P pole magnets in the rotor 1 (P is a positive integer, P≥4). Since the adjacent two pole magnets have a common tangential permanent magnet 13, the number of permanent magnets in the entire rotor 1 is 2P. Compared with the related art that requires 3P permanent magnets to be set to realize the P pole magnets in the rotor 1, the above structure can significantly reduce the number of permanent magnets in the rotor 1, thereby reducing the cost.

[0104] like Figure 5 and Figure 6As shown, the tangential permanent magnet 13 and the radial permanent magnet 14 are correspondingly arranged behind the rotor core, the rotor 1 and the stator 2 are assembled, the stator 2 includes a stator core 21, and the stator core 21 is coaxially arranged with the rotor core 12. The permanent magnet in the rotor 1 will excite two magnetic flux paths, which are described in detail below:

[0105] The first, the main flux path, refers to Figure 5 A first tangential permanent magnet 131 is provided in the rotor 1 (the first tangential permanent magnet 131 is any one of the multiple tangential permanent magnets 13). Inside the first tangential permanent magnet 131, the magnetic flux lines are directed from the S pole of the first tangential permanent magnet 131 to the N pole. Outside the first tangential permanent magnet 131, the N pole of the first tangential permanent magnet 131 leads to the magnetic flux lines. The magnetic flux lines sequentially pass through the rotor core 12 on the first side of the first tangential permanent magnet 131, the gap between the rotor 1 and the stator 2, the stator core 21, the gap between the stator 2 and the rotor core 12, the rotor core 12 on the second side of the first tangential permanent magnet 131, and return to the S pole of the first tangential permanent magnet 131, forming a closed loop.

[0106] The second type, the secondary flux path, refers to Figure 6 The rotor 1 is provided with a first tangential permanent magnet 131 (the first tangential permanent magnet 131 is any one of the multiple tangential permanent magnets 13), a first radial permanent magnet 141 and a second radial permanent magnet 142 (the magnetic flux lines of the first radial permanent magnet 141 are directed toward the axis of the shaft body 11, and the magnetic flux lines of the second radial permanent magnet 142 are directed away from the axis of the shaft body 11). Inside the first radial permanent magnet 141, the magnetic flux lines are directed from the S pole of the first radial permanent magnet 141 to the N pole. Outside the first radial permanent magnet 141, the N pole of the first radial permanent magnet 141 leads to the magnetic flux lines. It passes in sequence through the reinforcing rib 123 on the first side of the first tangential permanent magnet 131, the S pole of the first tangential permanent magnet 131, the N pole of the first tangential permanent magnet 131, the reinforcing rib 123 on the second side of the first tangential permanent magnet 131, the S pole of the second radial permanent magnet 142, the N pole of the second radial permanent magnet 142, the rotor core 12 on the first side of the first tangential permanent magnet 131, the gap between the rotor 1 and the stator 2, the stator core 21, the gap between the stator 2 and the rotor core 12, the rotor core 12 on the second side of the first tangential permanent magnet 131, and returns to the S pole of the first radial permanent magnet 141 to form a loop.

[0107] In practice, a coil winding is provided in the stator core 21, and alternating current is passed through the coil winding to excite a changing magnetic field. The magnetic field excited by the rotor 1 interacts with the changing magnetic field excited by the coil winding. Under the action of the magnetic force, the rotor 1 rotates, and a torque is output to the rotating part through the shaft 11, thereby driving the rotating part to rotate.

[0108] In a possible embodiment, the tangential permanent magnet 13 is an iron-needle-boron permanent magnet, and the radial permanent magnet 14 is a ferrite permanent magnet.

[0109] In implementation, reference Figure 4 In the rotor 1, the internal magnetic flux lines of the tangential permanent magnet 13 extend along the tangential direction of the rotor 1, and the internal magnetic flux lines of the radial permanent magnet 14 extend along the radial direction of the rotor 1. According to the distribution law of the external magnetic flux lines of the permanent magnet, when the magnetic flux lines of the two poles of the tangential permanent magnet 13 form a closed loop, most of the magnetic flux lines on the side away from the shaft 11 will pass through the gap between the stator 2 and the rotor 1. The tangential permanent magnet 13 has a magnetic gathering effect, while when the magnetic flux lines of the two poles of the radial permanent magnet 14 form a closed loop, only a small part of the magnetic flux lines will pass through the stator. The gap between the rotor 2 and the rotor 1, most of the loops formed by the magnetic flux lines stay inside the rotor core 12. Therefore, for the tangential permanent magnets 13 and the radial permanent magnets 14, the tangential permanent magnets 13 play a major role in improving the air gap magnetic density. Accordingly, the tangential permanent magnets 13 are set to be iron-needle-boron permanent magnets with high energy product and strong magnetic properties, and the radial permanent magnets 14 are set to be relatively inexpensive ferrite permanent magnets. This can control the material cost of the permanent magnets while improving the air gap magnetic density of the motor, thereby improving product competitiveness.

[0110] The tangential permanent magnet 13 may be any one of a cobalt-boron permanent magnet and a samarium-cobalt permanent magnet, which is not limited in the embodiment of the present disclosure.

[0111] Below, some optional structural features of the rotor 1 of the interior permanent magnet motor are introduced:

[0112] Structural feature 1. After the tangential permanent magnet 13 is assembled to the first slot body 121 , there may be a gap between the tangential permanent magnet 13 and the bottom of the first slot body 121 .

[0113] like Figure 2 As shown, the rotor core 12 has a plurality of first slot bodies 121 inside, and the plurality of first slot bodies 121 are distributed circumferentially around the shaft body 11. The shape and size of the tangential permanent magnets 13 match those of the first slot bodies 121. The plurality of tangential permanent magnets 13 are correspondingly arranged in different first slot bodies 121 and are connected to the rotor core 12. There is a gap 300 between one end of the tangential permanent magnet 13 close to the shaft body 11 and the bottom of the first slot body 121. That is, one end of the tangential permanent magnet 13 close to the shaft body 11 and the wall of the first slot body 121 close to the shaft body 11 are not in contact with each other, and there is a gap 300 between the two.

[0114] In implementation, when the tangential permanent magnet 13 is in contact with the wall of the first slot body 121 close to the shaft body 11, since the rotor core 12 has good magnetic conductivity, for the end of the tangential permanent magnet 13 close to the shaft body 11, the magnetic flux lines between its two poles can directly form a closed loop through the yoke of the rotor core 12, resulting in leakage magnetic flux. Therefore, a gap 300 is set between the end of the tangential permanent magnet 13 close to the shaft body 11 and the wall of the first slot body 121 close to the shaft body 11. The existence of the gap 300 can increase the magnetic resistance of the position where the end of the tangential permanent magnet 13 close to the shaft body 11 is located, thereby reducing the leakage magnetic flux of the tangential permanent magnet 13 and improving the air gap magnetic density.

[0115] Optionally, the rotor 1 may further include a magnetic blocking member 15 .

[0116] like Figure 4 As shown, a plurality of first slots 121 are circumferentially distributed around the shaft 11 inside the rotor core 12, and a plurality of tangential permanent magnets 13 are correspondingly arranged in different first slots 121. The rotor 1 further includes a plurality of magnetic blocking members 15, which are correspondingly arranged in different first slots 121. The magnetic blocking members 15 are arranged in the above-mentioned gap 300, that is, the two ends of the magnetic blocking member 15 are respectively in contact with one end of the tangential permanent magnet 13 close to the shaft 11 and the wall surface of the first slot 121 close to the shaft 11.

[0117] In this way, the connection strength between the tangential permanent magnets 13 and the rotor core 12 can be improved.

[0118] The material of the magnetic blocking component 15 can be various materials with low magnetic permeability, such as ceramic materials such as aluminum oxide, titanium oxide and tin oxide, or low magnetic permeability metal materials such as silver. The embodiment of the present disclosure does not limit the material of the magnetic blocking component 15.

[0119] Structural feature 2: For the end of the tangential permanent magnet 13 close to the shaft 11 , the distance to the end of the radial permanent magnet 14 close to the shaft 11 is not greater than the distance to the end of the radial permanent magnet 14 far from the shaft 11 .

[0120] like Figure 4 As shown, a plurality of tangential permanent magnets 13 are circumferentially distributed around the shaft 11 inside the rotor core 12, and each radial permanent magnet 14 is correspondingly arranged between two adjacent tangential permanent magnets 13, see Figure 4 , the radial distance from the first end face 13a of the tangential permanent magnet 13 to the shaft body 11 can be a first value, the radial distance from the first end face 14a of the radial permanent magnet 14 to the shaft body 11 can be a second value, and the radial distance from the second end face 14b of the radial permanent magnet 14 to the shaft body 11 can be a third value. Moreover, the difference between the third value and the first value is a first difference, the difference between the first value and the second value is a second difference, and the first difference is not less than the second difference.

[0121] Among them, the first end face 13a of the tangential permanent magnet 13 is the end face of the tangential permanent magnet 13 close to the shaft body 11, the first end face 14a of the radial permanent magnet 14 is the end face of the radial permanent magnet 14 close to the shaft body 11, and the second end face 14b of the radial permanent magnet 14 is the end face of the radial permanent magnet 14 away from the shaft body 11.

[0122] In this way, the magnetic resistance between the first end face 14a of the radial permanent magnet 14 and the first end face 13a of the tangential permanent magnet 13 can be made much smaller than the magnetic resistance between the first end face 14a of the radial permanent magnet 14 and the second end face 14b of the radial permanent magnet 14, thereby preventing the magnetic flux lines outside the radial permanent magnet 14 from directly forming a loop between the first end face 14a of the radial permanent magnet 14 and the second end face 14b of the radial permanent magnet 14, that is, reducing the leakage magnetic flux of the radial permanent magnet 14, thereby improving the air gap magnetic density.

[0123] The technical solution provided by the embodiments of the present disclosure includes at least the following beneficial effects:

[0124] The embodiment of the present disclosure provides a rotor 1 of an internal permanent magnet motor, in which a rotor core 12 is sleeved outside a shaft body 11. A plurality of tangential permanent magnets 13 are circumferentially distributed inside the rotor core 12 around the shaft body 11, and the directions of the magnetic flux lines of two adjacent tangential permanent magnets 13 are opposite. Each radial permanent magnet 14 is correspondingly arranged between two adjacent tangential permanent magnets 13. In addition, the rotor core 12 has a plurality of reinforcing ribs 123, each reinforcing rib 123 is correspondingly arranged between adjacent tangential permanent magnets 13 and radial permanent magnets 14, the magnetic flux lines of the radial permanent magnets 14 between the first magnetic pair 100 are in a direction away from the axis of the shaft body 11, the two adjacent tangential permanent magnets 13 with opposite magnetic flux lines form the first magnetic pair 100, and the two adjacent tangential permanent magnets 13 with opposite magnetic flux lines form the second magnetic pair 200; the magnetic flux lines of the radial permanent magnets 14 between the first magnetic pair 100 are in a direction away from the axis of the shaft body 11, and the magnetic flux lines of the radial permanent magnets 14 between the second magnetic pair 200 point to the axis of the shaft body 11, and the magnetic flux lines are in a direction of the internal magnetic flux lines of the permanent magnets. In this way, a tangential permanent magnet 13 is arranged between each two adjacent radial permanent magnets 14, and reinforcing ribs 123 are arranged on both sides of each radial permanent magnet 14. For any radial permanent magnet 14 whose magnetic flux lines are directed toward the axis of the shaft body 11, since the distance between its N pole and the S pole of the adjacent tangential permanent magnet 13 is closer than the distance between its N pole and the S pole of the radial permanent magnet 14, the magnetic resistance is smaller. When the magnetic flux lines led out from the N pole pass through the reinforcing rib 123, most of the magnetic flux lines will pass through the adjacent tangential permanent magnet 13 and the adjacent radial permanent magnet 14 in turn and then return to the S pole of the radial permanent magnet 14, rather than directly forming a closed loop from the N pole to the S pole of the radial permanent magnet 14, which means that the leakage magnetic flux of the radial permanent magnet 14 is reduced, and the air gap magnetic density can be improved.

[0125] An embodiment of the present disclosure provides an interior permanent magnet motor, which includes the above-mentioned rotor 1 and stator 2.

[0126] like Figure 7 As shown, the stator 2 includes a stator core 21 and a plurality of coil windings 22. The stator core 21 has a cylindrical structure. The stator core 21 is mounted on the outer ring of the rotor core 12, and there is a gap between the stator core 21 and the rotor core 12. A plurality of third slots 211 are distributed around the circumference of the shaft 11 inside the stator core 21. The plurality of third slots 211 are arranged at intervals, and the intervals between each two adjacent third slots 211 are equal. The inner wall of the third slot 211 has an insulating coating. The plurality of coil windings 22 are arranged in different third slots 211 and are fixedly connected to the stator core 21.

[0127] In one example, the coil winding 22 is an enameled wire, that is, the outer wall of the metal coil is covered with an insulating coating.

[0128] In this way, the safety of the built-in permanent magnet motor during use can be improved.

[0129] During implementation, the coil winding 22 is passed through alternating current to excite a changing magnetic field, and the magnetic field excited by the permanent magnet in the rotor 1 interacts with the changing magnetic field excited by the coil winding 22. Under the action of the magnetic force, the rotor 1 rotates, outputs torque to the rotating part through the shaft 11, and drives the rotating part to rotate.

[0130] An embodiment of the present disclosure provides an electric device, which includes the above-mentioned rotor 1, or includes the above-mentioned built-in permanent magnet motor.

[0131] The above description is only an optional embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A rotor (1) of an interior permanent magnet motor, characterized in that: The rotor (1) comprises a shaft (11), a rotor core (12), a plurality of tangential permanent magnets (13) and a plurality of radial permanent magnets (14); The rotor core (12) is sleeved outside the shaft body (11); The plurality of tangential permanent magnets (13) are circumferentially distributed around the shaft (11) inside the rotor core (12), and the directions of the magnetic flux lines of two adjacent tangential permanent magnets (13) are opposite; Each of the radial permanent magnets (14) is correspondingly arranged between two adjacent tangential permanent magnets (13); The rotor core (12) has a plurality of reinforcing ribs (123), each of the reinforcing ribs (123) being arranged between adjacent tangential permanent magnets (13) and radial permanent magnets (14); two adjacent tangential permanent magnets (13) with opposite magnetic flux lines form a first magnetic pair (100); and two adjacent tangential permanent magnets (13) with opposite magnetic flux lines form a second magnetic pair (200); the direction of the magnetic flux lines of the radial permanent magnets (14) between the first magnetic pair (100) is away from the axis of the shaft (11); the direction of the magnetic flux lines of the radial permanent magnets (14) between the second magnetic pair (200) is directed toward the axis of the shaft (11); and the direction of the magnetic flux lines is the direction of the internal magnetic flux lines of the permanent magnets.

2. The rotor (1) according to claim 1, characterized in that The rotor core (12) has a plurality of first slot bodies (121) and a plurality of second slot bodies (122) inside; The plurality of first slot bodies (121) are distributed circumferentially around the shaft body (11), and the first slot bodies (121) are used to accommodate the tangential permanent magnets (13); Each of the second slot bodies (122) is correspondingly arranged between two adjacent first slot bodies (121), and the second slot bodies (122) are used to accommodate the radial permanent magnets (14).

3. The rotor (1) according to claim 2, characterized in that The rotor core (12) further comprises a connecting rib (124), wherein the connecting rib (124) is located on a side of an end surface of the first slot body (121) away from the shaft body (11), and two ends of the connecting rib (124) are respectively connected to two opposite wall surfaces of the first slot body (121) in a tangential direction.

4. The rotor (1) according to claim 3, characterized in that The thickness of the connecting rib (124) is smaller than the thickness of the reinforcing rib (123).

5. The rotor (1) according to claim 2, characterized in that There is a gap (300) between the tangential permanent magnet (13) and the wall surface of the first slot body (121) close to the shaft body (11).

6. The rotor (1) according to claim 5, characterized in that The rotor (1) further comprises a magnetic blocking member (15), wherein the magnetic blocking member (15) is located in the gap (300), and two ends of the magnetic blocking member (15) respectively abut against the tangential permanent magnet (13) and the wall surface of the first slot body (121) close to the shaft body (11).

7. The rotor (1) according to claim 1, characterized in that The radial distance from the first end face (13a) of the tangential permanent magnet (13) to the shaft body (11) is a first value, the radial distance from the first end face (14a) of the radial permanent magnet (14) to the shaft body (11) is a second value, the radial distance from the second end face (14b) of the radial permanent magnet (14) to the shaft body (11) is a third value, the difference between the third value and the first value is a first difference, the difference between the first value and the second value is a second difference, and the first difference is not less than the second difference; The first end face (13a) of the tangential permanent magnet (13) is the end face of the tangential permanent magnet (13) close to the shaft (11), the first end face (14a) of the radial permanent magnet (14) is the end face of the radial permanent magnet (14) close to the shaft (11), and the second end face (14b) of the radial permanent magnet (14) is the end face of the radial permanent magnet (14) away from the shaft (11).

8. The rotor (1) according to claim 1, characterized in that The shaft body (11) and the rotor core (12) are connected via a spline.

9. An internal permanent magnet motor, characterized in that: The interior permanent magnet motor comprises a rotor (1) as claimed in any one of claims 1 to 8.

10. An electric device, characterized in that: The electric device comprises a rotor (1) as claimed in any one of claims 1 to 8 or an interior permanent magnet motor as claimed in claim 9.

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