CN117728608A - Motor with a motor housing - Google Patents

Abstract

An embodiment of the present application provides a motor, including: the shell assembly is provided with bearing chambers at two axial ends; a rotor assembly disposed within the housing assembly, the rotor assembly including a rotor core; two first heat insulating parts are arranged on the outer sides of the bearing chambers respectively and used for isolating heat exchange between the rotor iron core and the bearing chambers.

Description

Motor with a motor housing

Technical Field

The application relates to the technical field of motors, in particular to a motor.

Background

During the operation of the motor, the temperature of key parts such as a rotor core, a bearing and the like rises to influence the output power of the motor, so that the motor is usually required to be cooled. However, since the heat generation amounts of the rotor core, the bearing, and the like are different and the optimal operating temperatures of the respective portions are different, it is difficult for the conventional cooling structure to control the temperatures of the respective portions within the optimal operating temperatures while cooling, thereby affecting the output efficiency of the motor.

Disclosure of Invention

In view of this, it is desirable to provide a motor capable of improving the output efficiency of the motor.

To achieve the above object, an embodiment of the present application provides a motor, including:

The shell assembly is provided with bearing chambers at two axial ends;

a rotor assembly disposed within the housing assembly, the rotor assembly including a rotor core;

and the two first heat insulation pieces are respectively arranged outside the bearing chambers and used for isolating heat exchange between the rotor core and the bearing chambers.

In some embodiments, the first heat insulator surrounds the bearing chamber exterior sidewall and defines a first air duct with the bearing chamber exterior sidewall.

In some embodiments, a second through air channel is formed in the rotor assembly, the second air channel is communicated with the first air channel, an air inlet and an air outlet are formed in the shell assembly, the air inlet is communicated with one first air channel, and the air outlet is communicated with the other first air channel.

In some embodiments, the housing assembly forms a boss surrounding the bearing chamber to one side of the first heat shield, and the first heat shield is covered outside the boss and is in clearance fit with the boss.

In some embodiments, the motor includes a stator assembly disposed between the housing assembly and the rotor assembly, and a second thermal shield disposed between the stator assembly and the rotor assembly for isolating heat exchange between the stator assembly and the rotor assembly.

In some embodiments, the second insulation comprises an insulation layer overlying the inner surface of the stator assembly.

In some embodiments, the stator assembly includes a stator core and stator windings, the stator winding portions extending from axial ends of the stator core to form end windings;

the second heat insulator includes a heat insulating cylinder provided inside the end winding to insulate the end winding from heat exchange with the bearing chamber.

In some embodiments, the insulating cartridge is sealingly connected between the housing assembly and the stator assembly.

In some embodiments, the two axial ends of the rotor assembly, the heat insulation cylinder, the first heat insulation piece and the shell assembly enclose a cavity, and a through hole is arranged in the rotor assembly and communicated with the cavity to jointly form a circulating air channel.

In some embodiments, two of the first heat shields are coupled to the rotor assembly, and the outer sidewall of at least one of the two first heat shields has fan blades formed thereon.

In some embodiments, the motor includes a stator assembly including a stator core and stator windings, the stator winding portions extending from axial ends of the stator core to form end windings with gaps between wires of the end windings, and a thermally conductive member at least partially filling the gaps of the end windings.

In some embodiments, the heat conductive member includes a sleeve sleeved outside the end winding and a first heat conductive filling part filled in a gap of the end winding and between the end winding and the sleeve;

wherein the thermal conductivity of the material of the sleeve is greater than the thermal conductivity of the material of the first thermally conductive filler.

In some embodiments, the sleeve comprises a sleeve body and a heat dissipation tooth plate group protruding out of the outer peripheral surface of the sleeve body.

In some embodiments, a third air channel is defined between the housing assembly and the stator core, and the heat dissipation tooth set is disposed in the third air channel.

In some embodiments, the sleeve comprises a sleeve body and a plurality of heat conducting ribs which are arranged on the sleeve body and protrude inwards, and each heat conducting rib is arranged at intervals along the circumferential direction of the sleeve body.

In some embodiments, the rotor assembly comprises

A rotor core provided with an installation groove therein;

the permanent magnet is arranged in the mounting groove and comprises a first permanent magnet unit and a second permanent magnet unit, the first permanent magnet unit is positioned at one end, far away from the rotation axis, of the second permanent magnet unit along the radial direction of the rotor core, the residual magnetic induction intensity of the material of the first permanent magnet unit is smaller than that of the material of the second permanent magnet unit, and the first permanent magnet unit and the second permanent magnet unit are bonded through an insulating layer.

In some embodiments, the first permanent magnet unit is made of an adhesive neodymium iron boron material, and the second permanent magnet unit is made of a sintered neodymium iron boron material.

In some embodiments, the magnetization directions of the first permanent magnet unit and the second permanent magnet unit are the same.

In some embodiments, the first permanent magnet unit has a smaller size than the second permanent magnet unit in a direction perpendicular to the magnetizing direction.

In some embodiments, the end surface of the first permanent magnet unit on the side far away from the rotation axis along the magnetizing direction is a first end surface, the end surface of the second permanent magnet unit on the side far away from the rotation axis along the magnetizing direction is a second end surface, and the second end surface is beyond or flush with the first end surface along the magnetizing direction.

In some embodiments, the mounting grooves are arranged in pairs, and a spacing cavity is arranged between one end of at least part of the two mounting grooves near the rotation axis, and a non-magnetic block is arranged in the spacing cavity

According to the motor, the heat insulation assembly is arranged between the rotor core and the bearing chamber, and the heat exchange between the rotor core and the bearing chamber is isolated, so that the heat exchange between the rotor core and the bearing chamber can be reduced, the temperature difference between the rotor core and the bearing chamber is maintained, the rotor core and the bearing chamber are kept at the optimal working temperature, and the output efficiency of the motor is improved.

Drawings

FIG. 1 is a partial cross-sectional view of an electric machine according to an embodiment of the present application;

FIG. 2 is a schematic diagram of the airflow direction of the motor shown in FIG. 1;

FIG. 3 is a first partial schematic view of the motor of FIG. 1;

FIG. 4 is a schematic diagram of an end cap structure of the motor of FIG. 1;

FIG. 5 is a cross-sectional view of the end cap of FIG. 4;

FIG. 6 is a schematic view of a portion A of the end cap of FIG. 5;

FIG. 7 is a partial schematic view of an electric motor according to an embodiment of the present application;

FIG. 8 is a cross-sectional view of a stator assembly of an electric machine according to an embodiment of the present application;

FIG. 9 is another structural schematic diagram of a stator assembly of an electric machine according to an embodiment of the present disclosure;

FIG. 10 is a second partial schematic view of the motor of FIG. 1;

FIG. 11 is a schematic view of the sleeve of the motor of FIG. 1;

FIG. 12 is a partial cross-sectional view of a sleeve of the motor of FIG. 11;

FIG. 13 is a schematic view of a rotor assembly and a stator assembly of an electric machine according to an embodiment of the present disclosure;

FIG. 14 is a schematic view of the permanent magnet of the motor of FIG. 13;

fig. 15 is a side view of a permanent magnet of the motor of fig. 14.

Description of the reference numerals

A housing assembly 10; a bearing chamber 10a; an air inlet 10b; an air outlet 10c; a second air outlet 10d; a boss 11; a housing 12; an end cap 13; an end face portion 131; a first interlayer 1311; a second interlayer 1312; an inner ring portion 132; an outer ring portion 133; a fourth air duct 13a; annular ribs 134;

A rotor assembly 20; a second air duct 20a; a cavity 20b; a circulation duct 20d; a rotor core 21; a mounting groove 21a; a compartment 21b; a permanent magnet 22; a first permanent magnet unit 221; a first end surface 221a; a second permanent magnet unit 222; a second end face 222a; an insulating layer 223; a nonmagnetic block 23; a rotating shaft 24;

a first heat insulator 30; a first air duct 30a; a fan blade 31;

a stator assembly 40; a stator core 41; a core body 411; tooth slots 411a; slot wedge 412; a stator winding 42; end windings 421; a third air duct 40a;

a second heat insulator 50; a heat insulating layer 51; a heat insulating cylinder 52;

a heat conductive member 60; a sleeve 61; a sleeve body 611; fin group 612; a connecting piece 6121; a heat dissipation portion 6122; a first thermally conductive filler 62; a heat conductive rib 613; lugs 614; the second heat conductive filler 63.

Detailed Description

Embodiments of the present application are described in further detail below with reference to the accompanying drawings and examples. The following examples are illustrative of the present application but are not intended to limit the scope of the present application.

In the description of the embodiments of the present application, it should be noted that the terms "top," "bottom," and the like indicate an orientation or a positional relationship based on the orientation or the positional relationship shown in fig. 5, and are merely for convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the devices or elements to be referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the embodiments of the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Referring to fig. 1, an embodiment of the present application provides an electric motor, which includes a housing assembly 10, a rotor assembly 20, and two first heat insulators 30.

The type of motor is not limited. For example, it may be one of an electromagnetic motor, a dc motor, a permanent magnet motor, a brushless dc motor, etc., and the embodiment of the present application is exemplified by a permanent magnet motor.

The housing assembly 10 has bearing chambers 10a at both axial ends. The bearing housing 10a is used for mounting a bearing.

In some embodiments, referring to fig. 1 and 2, the housing assembly 10 includes a housing 12 and end caps 13 disposed at both axial ends of the housing 12, and a bearing chamber 10a at least one end is disposed on the end caps 13.

The rotor assembly 20 is disposed within the housing assembly 10. The rotor assembly 20 includes a rotating shaft 24, and both ends of the rotating shaft 24 are penetrated into the bearing chamber 10a and supported by bearings in the bearing chamber 10a. It will be appreciated that when the shaft 24 rotates, the inner race of the bearing will be driven into rotation, and friction between the inner race and the outer race of the bearing will cause the bearing to heat, which is conducted through the wall of the bearing chamber 10a to the outside of the bearing chamber 10a.

The rotor assembly 20 includes a rotor core 21. The rotor core 21 is provided on the rotating shaft 24, and the rotor core 21 rotates following the rotating shaft 24.

Two first heat insulators 30 are provided outside the bearing chambers 10a, respectively, for isolating heat exchange between the rotor core 21 and the bearing chambers 10 a. That is, one first heat insulator 30 is provided outside each bearing chamber 10 a.

In the above embodiment, the first heat insulator 30 makes almost no heat exchange between the rotor core 21 and the bearing chamber 10a, so that the operating temperatures of the rotor core 21 and the bearing chamber 10a are maintained at the respective optimum operating temperatures, thereby improving the output efficiency of the motor.

It is understood that the first heat insulator 30 may cover the outer side wall of the bearing chamber 10a, or cover the axial end portion of the rotor core 21.

For example, referring to fig. 3, the first heat insulation member 30 is disposed around the outer side wall of the bearing chamber 10a, and defines a first air duct 30a together with the outer side wall of the bearing chamber 10 a. It will be appreciated that the first air duct 30a is located outside the bearing housing 10a, i.e. between the rotor core 21 and the bearing housing 10a, so that heat exchange between the rotor core 21 and the bearing housing 10a can be further reduced. And, the heat of the bearing is transferred to the first air duct 30a through the side wall of the bearing chamber 10a to achieve cooling of the bearing chamber 10 a.

It is understood that the air inlet and the air outlet of the first air duct 30a may be directly connected to the outside of the motor. That is, the air outside the motor flows into the first air duct 30a from the air inlet and flows out of the motor from the air outlet of the first air duct 30a.

In some embodiments, a second air duct 20a is formed on the rotor assembly 20, the second air duct 20a is communicated with the first air duct 30a, an air inlet 10b and an air outlet 10c are formed on the housing assembly 10, the air inlet 10b is communicated with one first air duct 30a, and the air outlet 10c is communicated with the other first air duct 30a. Air outside the motor enters a first air duct 30a from an air inlet 10b on the shell, and flows out of the motor through the first air duct 30a, the second air duct 20a, the other first air duct 30a and an air outlet 10c in sequence.

It is to be understood that the positions where the air inlet 10b and the air outlet 10c are provided are not limited. For example: the air inlet 10b and the air outlet 10c are provided on both end caps 13, respectively.

In some embodiments, referring to fig. 4, the end cover 13 includes an end surface portion 131, an inner ring portion 132 surrounding an inner edge of the end surface portion 131, and an outer ring portion 133 surrounding an outer edge of the end surface portion 131, where the inner ring portion 132 surrounds the bearing chamber 10a with an open bottom.

Referring to fig. 5 and 6, the end surface portion 131 includes a first interlayer 1311 and a second interlayer 1312 disposed on top of the first interlayer 1311, and a fourth air duct 13a is enclosed between the first interlayer 1311 and the second interlayer 1312, and the fourth air duct 13a communicates with the air inlet 10b and the first air duct 30a. Wherein the air intake 10b is provided on the side wall of the outer ring portion 133. Thus, air flows from the air inlet 10b into the fourth air duct 13a, and from the fourth air duct 13a into the first air duct 30a at one axial end.

It will be appreciated that the manner in which the housing assembly 10 is mated with the first thermal shield 30 is not limited, e.g., the first thermal shield 30 is sealingly coupled to the housing assembly 10.

For example, referring to fig. 3 and 6, the housing assembly 10 is formed with a boss 11 surrounding the bearing chamber 10a to one side of the first heat insulator 30, and the first heat insulator 30 is covered outside the boss 11 and is clearance-fitted with the boss 11, thereby reducing heat conduction between the housing assembly 10 and the first heat insulator 30.

In this embodiment, in the radial direction of the bearing chamber 10a, there is an overlapping area of the boss 11 and the first heat insulator 30, the overlapping area having a certain extension length in the axial direction of the bearing chamber 10a, so that dust can be prevented from entering the inside of the first air duct 30a in the radial direction.

The first heat insulator 30 may be located inside the boss 11.

The gap size is not limited, and the gap between the first heat insulating member 30 and the boss 11 in the overlapping region is 0.5mm to 2mm after the boss 11 is in clearance fit with the first heat insulating member 30, for example.

It will be appreciated that the first thermal shield 30 is a hollow, cage structure, and in some embodiments, the first thermal shield 30 increases in size from an end proximal to the rotor assembly 20 to an end distal from the rotor assembly 20.

It will be appreciated that the first insulator 30 is fixed to the rotor assembly 20, the first insulator 30 rotates in synchronism with the rotor assembly 20, and the boss 11 is relatively fixed to the housing assembly 10. That is, the first heat insulating member 30 and the boss 11 can rotate relatively, and the clearance fit can enable the two to rotate relatively, and the clearance after the clearance fit is limited in a certain range, so that dust is further prevented from entering the first air duct 30a.

The length of the overlap region in the axial direction of the first heat insulator 30 is not limited. Illustratively, the extension length is generally 2mm to 20mm, so that the occupation of space is reduced while a certain dustproof effect is ensured, and meanwhile, the extension length of the boss 11 and the first heat insulating member 30 in the overlapping region is controlled within a certain range, so that materials can be saved to a certain extent, and the cost is reduced.

Referring to fig. 1, the motor includes a stator assembly 40 and a second heat insulating member 50, wherein the stator assembly 40 is disposed between the housing assembly 10 and the rotor assembly 20, and the second heat insulating member 50 is disposed between the stator assembly 40 and the rotor assembly 20 for insulating heat exchange between the stator assembly 40 and the rotor assembly 20, and it is understood that the second heat insulating member 50 isolates heat of the stator assembly 40 from being transferred and spread in a direction of the rotor assembly 20, thereby facilitating thermal management of the stator assembly 40 and the rotor assembly 20, and controlling the two at a preferred operating temperature.

Referring to fig. 7, the second insulation member 50 includes an insulation layer 51 covering the inner surface of the stator assembly 40. The heat insulating layer 51 may be a paint having a heat insulating function, or may be an aerosol. It will be appreciated that there is an air gap between the stator assembly 40 and the rotor assembly 20, with the insulation layer 51 being in the air gap.

It will be appreciated that the thickness of the insulating layer 51 should be less than the radial dimension of the air gap, and in some embodiments, the thickness of the insulating layer 51 should be less than half the radial dimension of the air gap. The thickness of the insulating layer 51 is, for example, 0.5mm to 5mm.

Illustratively, the stator assembly 40 includes a stator core 41 and stator windings 42, the stator windings 42 partially protruding from both axial ends of the stator core 41 to form end windings 421. That is, the end windings 421 are part of the stator windings 42, and are located at both axial ends of the stator core 41.

The second heat insulator 50 includes a heat insulating cylinder 52, and the heat insulating cylinder 52 is surrounded on the inner side of the end winding 421 to insulate the end winding 421 from heat exchange with the bearing chamber 10 a. Thereby facilitating thermal management of bearing housing 10a and end windings 421 of stator assembly 40.

In the radial direction, the bearing chamber 10a is located radially inward of the stator assembly 40, that is, radially inward of the end windings 421. When the heat insulating tube 52 is disposed around the inside of the end winding 421, the heat insulating tube 52 is disposed between the end winding 421 and the bearing chamber 10a, thereby preventing the stator heat from radiating to the bearing chamber 10 a.

For example, referring to fig. 8 and 9, the stator core 41 includes a core body 411 and a plurality of slot wedges 412. The core body 411 is provided with a plurality of slots 411a spaced along the circumferential direction of the rotor assembly 20, and the stator winding 42 is arranged to pass through the slots 411a in a reciprocating manner.

The slot wedge 412 extends in the axial direction and closes the inner side surface of the slot 411 a. The position of the stator winding 42 in the tooth slot 411a is restrained by the wedge 412, which is beneficial to the stator winding 42 to keep fixed, reduces the probability of the stator winding 42 falling out of the tooth slot 411a, and ensures that the motor works stably.

The heat insulation barrel 52, the slot wedge 412 and the iron core body 411 are bonded through the insulating bonding coating, and the insulating bonding coating is coated at the joint positions of the heat insulation barrel 52, the slot wedge 412 and the iron core body 411, so that the heat insulation barrel 52, the slot wedge 412 and the iron core body 411 are connected together, the insulating performance is improved, and the isolation function is achieved.

The specific material of the insulating adhesive coating is not limited, for example, silica gel, so that the insulating adhesive coating has good heat conducting property and improves heat dissipation efficiency.

Illustratively, the insulation cartridge 52 is sealingly connected between the housing assembly 10 and the stator assembly 40. The specific manner in which the insulating cartridge 52 is sealingly coupled to the stator assembly 40 is not limited. The specific manner in which the insulating cartridge 52 is sealingly coupled to the housing assembly 10 is not limited.

For example, referring to fig. 8, the heat insulating cylinder 52 includes a heat insulating cylinder body 521 and an elastic connection member 522, the heat insulating cylinder body 521 extends in an axial direction, the elastic connection member 522 is in a ring shape extending in a circumferential direction of the rotor assembly 20, one end of the heat insulating cylinder body 521 is connected with the stator core 41 in a sealing manner, the other end is connected with the elastic connection member 522, and the elastic sealing member 522 is connected with the housing assembly 10 in a sealing manner, that is, the connection position of the heat insulating cylinder 52 and the housing assembly 10 is completely sealed by the elastic connection member 522 in the circumferential direction.

The elastic connection 522 is elastically stretchable at least in the axial direction. During installation of the housing assembly 10 and the stator assembly 40, the resilient coupling 522 is compressed in axial dimension, which, on the one hand, facilitates adapting the insulation cartridge 52 to axial dimensional tolerances between different housing assemblies 10 and stator assemblies 40; on the other hand, the elastic connection member 522 expands and contracts in the axial direction so that the elastic connection member 522 is held in axial abutment with the heat insulating cylinder body 521 and the housing assembly 10, respectively, in the axial direction, which is advantageous in improving the sealing performance.

The elastic connection member 522 is made of an elastic material, and the specific material is not limited, for example, temperature-resistant rubber.

The specific manner in which the connection between the housing assembly 10 and the resilient connector 522 is achieved is not limited.

For example, referring to fig. 7, an annular rib 134 is disposed on a side of the end cover 13 axially adjacent to the stator core 41, the annular rib 134 extends circumferentially, an open slot is disposed on a side of the elastic connection member 522 facing away from the heat insulation cylinder 521, and the annular rib 134 is embedded in the open slot and is in sealing fit with the elastic connection member 522.

For relatively equalizing the temperature of the rotor assembly, for example, please refer to fig. 7, the two axial ends of the rotor assembly, the heat insulation tube 52, the first heat insulation member 30, and the housing assembly 10 enclose a cavity 20b, and a through hole (not shown) is provided in the rotor assembly, and the through hole communicates with the cavity 20b to jointly form the circulation duct 20d. It will be appreciated that air can circulate within the circulation duct 20d, i.e. air can flow from the cavity 20b at one end into the cavity 20b at the other end through the through-holes and flow back from the cavity 20b at the other end to the cavity 20b at one end through the through-holes, thereby making the operating temperature distribution of the rotor assembly more uniform. Wherein the through hole is opened in the stator core 41, which penetrates the stator core 41 in the axial direction.

It should be noted that, the circulating air duct 20d and the second air duct 20a in the rotor assembly are two independent air ducts, and the heat in the circulating air duct 20d can be transferred to the second air duct 20a and be sent out from the motor by the air in the second air duct 20 a.

It should be noted that, the number of the through holes and the second air channels 20a is not limited, and in an exemplary embodiment, the number of the through holes and the second air channels 20a are all a plurality of through holes and the second air channels 20a in a one-to-one correspondence, and the heat dissipation effect of the rotor assembly can be further improved by the plurality of through holes and the second air channels 20 a.

The distribution manner of the plurality of through holes and the plurality of second air channels 20a on the rotor core is not limited, and the through holes and the second air channels 20a are arranged at intervals in the circumferential direction of the rotor core, so that the distribution of the through holes and the second air channels 20a is more uniform, each region of the rotor core can uniformly dissipate heat, and the situation that local temperature is too high inside the rotor core can be avoided to a certain extent.

To accelerate the air flow rate in the circulation path, illustratively, two first heat insulators 30 are coupled to the rotor assembly 20, and fan blades 31 are formed on an outer sidewall of at least one of the two first heat insulators 30. In this way, the rotor assembly rotates under the working state, and the first heat insulation member 30 rotates along with the rotation, so that the fan blades 31 rotate, and the air flow in the circulation channel is accelerated.

It is understood that the fan blade 31 may be disposed on two first heat insulation members 30, or may be disposed on one of the first heat insulation members 30. So as to meet the air circulation. In some embodiments, the fan blade 31 is disposed on the first heat insulating member 30 near the air inlet.

Wherein, the quantity of flabellum 31 is a plurality of, and a plurality of flabellums 31 evenly distribute in the circumference of first thermal-insulated piece 30, so for the wind-guiding effect is more even, simultaneously, the weight distribution in first thermal-insulated piece 30 circumference is also more even, and the reliability is better.

It is understood that the number of the fan blades 31 is not limited, and may be designed according to the heat dissipation requirement. In some embodiments, the number of fan blades 31 is six.

The first heat insulator 30 and the fan blades 31 may be formed integrally, for example, without limitation, and the integrally formed structure is excellent in integrity and high in reliability.

The shape of the fan blade 31 is not limited. Illustratively, the fan blades 31 may be configured as straight plates, such that the motor may drive the airflow circulation during either forward or reverse rotation.

In some embodiments, when the motor can only rotate in a single direction, the fan blade 31 can be curved according to the flow path of the external airflow, so as to enhance the flow guiding effect of the fan blade 31.

As can be appreciated, referring to fig. 10, for the stator winding 42, i.e., the end winding 421, beyond the axial end of the stator core 41, the heat of the end winding 421 can be dissipated only through the heat transfer path released into the air, resulting in a very low efficiency of heat dissipation, resulting in heat accumulation and a reduction in motor efficiency, since it is directly exposed to the air and is not in contact with the rapidly heat-transmissible substance.

In this regard, illustratively, the stator winding 42 partially extends from both axial ends of the stator core 41 to form end windings 421 with gaps between the individual wires of the end windings 421. The motor comprises a heat conducting member 60, the heat conducting member 60 at least partially filling the gaps of the end windings 421.

The heat of the end winding 421 can be quickly transferred to the heat conductive member 60. The heat dissipation is performed outwards by the heat conducting member 60, so that the heat of the end winding 421 can be transferred outwards relatively uniformly, and the reduction of the service life caused by local overhigh temperature can be avoided.

In some embodiments, part or all of the outer peripheral surface of the heat conducting member 60 is used to form part of the surface of the third air duct 40a through which air flows. That is, at least part of the outer peripheral surface of the heat conductive member 60 can transfer heat to the air in the third air duct 40a, thereby improving the heat dissipation efficiency of the end winding 421.

The third duct 40a is not limited in the molding manner. In some embodiments, a third air duct 40a is defined between the stator core 41 and the housing assembly 10. The air flows in the third air duct 40a to take away heat of the heat conductive member 60 and the stator assembly 40.

One end of the housing assembly 10 is provided with an air inlet 10b communicating with the third air duct 40a, and the other end of the housing assembly 10 is provided with a second air outlet 10d communicating with the third air duct 40a. In this way, air flows into the motor from one end of the housing assembly 10, and sequentially passes through the outer circumferential surface of the heat conducting member 60 at one end of the stator core 41, the outer circumferential surface of the stator core 41, and the outer circumferential surface of the heat conducting member 60 at the other end of the stator core 41, and heat exchange is generated between the air and the heat conducting member, so that rapid heat dissipation and temperature reduction are realized, and the heat dissipation characteristic of the motor is greatly improved.

The structure of the heat conductive member 60 is not limited.

In some embodiments, the heat conductive member 60 is a first heat conductive filling portion 62, and the first heat conductive filling portion 62 fills in the gap of the end winding 421 and wraps the end winding 421. The first heat conductive filling part 62 may be a silicone grease material.

In some embodiments, the heat conducting member 60 includes a sleeve 61 and a first heat conducting filler 62, the sleeve 61 is sleeved on the end winding 421, i.e. the sleeve 61 is disposed on the outer side of the end winding 421, it being understood that the outer side is the side of the end winding 421 close to the rotor assembly 20, and the inner side is the side of the end winding 421 facing away from the rotor assembly 20. The first heat conductive filling portion 62 fills in the gap of the end winding 421 and between the end winding 421 and the sleeve 61. At this time, part or all of the outer peripheral surface of the sleeve 61 forms part of the surface of the third air duct 40a, and the heat of the end winding 421 is transferred to the sleeve 61 through the first heat-conductive filling portion 62, and is cooled by heat exchange between the sleeve 61 and the cooling medium. Wherein, the thermal conductivity of the material of the sleeve 61 is greater than that of the first thermal conductive filling part 62, so as to improve the heat exchange efficiency of the thermal conductive member 60 and the cooling medium, that is, improve the heat dissipation efficiency of the stator winding 42.

In some embodiments, the heat insulation cylinder 52, the sleeve 61 and the stator core 41 enclose a cavity, and the first heat-conducting filling portion 62 is filled in the cavity, so as to facilitate molding of the first heat-conducting filling portion 62.

Specifically, during the preparation process, the sleeve 61 and the heat insulating cylinder 52 are fixed to the stator core 41, so that the sleeve 61, the heat insulating cylinder 52 and the stator core 41 enclose a cavity. The end of the motor is directed upwards, and the liquid heat conductive filler is filled into the cavity and floods the end winding 421, and after it is solidified, the first heat conductive filler 62 at one end is formed. The other end of the motor is turned up and the first heat conductive filler 62 at the other end is formed after repeated filling.

It will be appreciated that the configuration of the sleeve 61 is not limited, for example: the sleeve 61 includes a hollow sleeve body 611, and exchanges heat with air through the outer circumferential surface of the sleeve body 611. The sleeve body 611 has a cylindrical structure with two axial ends penetrating.

In some embodiments, referring to fig. 11, the sleeve 61 includes a sleeve body 611 and a heat dissipation fin set 612 protruding from an outer peripheral surface of the sleeve body 611. The protruding fin group 612 increases the heat radiation area of the sleeve 61, and accelerates the heat exchange speed with the cooling medium.

The fin group 612 is disposed in the third air duct 40a, so as to improve heat exchange efficiency.

Specifically, the air flows into the third air duct 40a, and flows through one heat dissipation fin set 612, the stator assembly 40, and the other heat dissipation fin set 612, so that the heat exchange area with the air is greatly increased, and the heat dissipation efficiency is improved.

It is understood that the number of the fin groups 612 is not limited, and for example, the number of the fin groups 612 is one, and is disposed around the outer circumferential surface of the sleeve body 611.

In some embodiments, the number of the fin groups 612 is plural, and the fin groups 612 are circumferentially spaced along the outer circumferential surface of the sleeve body 611, and each fin group 612 corresponds to each third air duct 40a one by one.

It will be appreciated that the sleeve 61 is fixedly connected to the stator core 41. In some embodiments, the sleeve 61 includes lugs 614 that connect to the sleeve barrel 611. The lugs 614 are located at end surfaces of the stator core 41, and the lugs 614 are fastened to the stator core 41 by fasteners.

For example, referring to fig. 12, the heat dissipation fin set 612 includes a connection piece 6121 and a heat dissipation portion 6122 disposed on the connection piece 6121, where one surface of the connection piece 6121 facing away from the heat dissipation portion 6122 is attached to the outer peripheral surface of the sleeve body 611. Heat is transferred from the sleeve body 611 to the connection piece 6121, and is transferred to the heat dissipation portion 6122 via the connection piece 6121. Wherein, the connecting piece 6121 is formed with a clamping groove (not shown in the figure), the openings of the clamping groove are distributed along the axial direction, and the clamping groove is clamped with one end of the sleeve body 611 so as to quickly install and connect the radiating fin group 612.

To exclude air between the connection piece 6121 and the sleeve barrel 611 and improve heat conduction efficiency, in some embodiments, a second heat conduction filling portion 63 is filled between the connection piece 6121 and the outer peripheral surface of the sleeve barrel 611. The second heat conductive filling portion 63 is a gel-type heat conductive material.

Referring to fig. 11, in order to improve the heat transfer efficiency between the sleeve body 611 and the first heat conductive filling portion 62. In some embodiments, the sleeve 61 includes a plurality of heat-conducting ribs 613 disposed on an inner wall of the sleeve body 611 and protruding inwards, each heat-conducting rib 613 is disposed at intervals along the circumferential direction of the sleeve body 611, and the first heat-conducting filling portion 62 is filled between adjacent heat-conducting ribs 613 and covers each heat-conducting rib 613. Thereby increasing the contact area between the first heat-conducting filling part 62 and the sleeve body 611, improving the heat exchange speed and enhancing the structural strength of the sleeve 61.

It will be appreciated that the sleeve body 611 and the thermally conductive ribs 613 may be connected by welding or integrally cast.

Referring to fig. 13, the rotor assembly 20 includes a permanent magnet 22, and the permanent magnet 22 is capable of generating a magnetic field. It will be appreciated that the permanent magnet 22 has the characteristics of high permeability and low resistivity, and that the eddy currents generated when the permanent magnet 22 is subjected to the higher harmonic magnetic field are based on the skin effect, and the eddy currents are greater the further the portion of the permanent magnet 22 is from the axis of rotation of the rotor structure.

For this, illustratively, a mounting groove 21a is provided in the rotor core 21, and the permanent magnet 22 is provided in the mounting groove 21 a. The mounting slots 21a provide mounting locations for the permanent magnets 22 and limit the position of the permanent magnets 22 to avoid magnetic field disturbances caused by movement of the rotor assembly 20 during rotation.

It will be appreciated that the rotor core 21 itself is part of the magnetic circuit of the motor and is made of laminated silicon steel sheets which are insulated from each other to reduce eddy current and hysteresis losses during operation of the rotor assembly 20.

It is understood that the rotor core 21 and the permanent magnet 22 can rotate together.

The specific position of the mounting groove 21a in the rotor core 21 is not limited, and for example, the mounting groove 21a is located inside the rotor core 21 and extends in the axial direction of the rotor core 21.

It is understood that the number of permanent magnets 22 and the number of mounting grooves 21a are plural, and the numbers of the two are identical and are arranged in one-to-one correspondence.

Referring to fig. 13 and 14, at least part of the permanent magnet 22 includes a first permanent magnet unit 221 and a second permanent magnet unit 222, the first permanent magnet unit 221 is located at least at one end of the second permanent magnet unit 222 away from the rotation axis in the radial direction of the rotor core 21, that is, one end of the second permanent magnet unit 222 is further away from the rotation axis of the rotor core 21 than the other end in the radial direction of the rotor core 21, and the first permanent magnet unit 221 is disposed at the one end such that the first permanent magnet unit 221 forms one end of the permanent magnet 22 outside in the radial direction of the rotor.

The eddy currents acting on the first permanent magnet unit 221 are larger than the eddy currents acting on the second permanent magnet unit 222. Therefore, the second permanent magnet unit 222 is not located in the main area affected by the higher harmonic magnetic field, and only a part of the leakage flux passes through the second permanent magnet unit 222.

The remanence induction intensity of the material of the first permanent magnet unit 221 is smaller than the remanence induction intensity of the material of the second permanent magnet unit 222. The residual magnetic induction intensity refers to the magnetization intensity which can be still maintained in the original external magnetic field direction after an object is magnetized to be saturated by the external magnetic field and the external magnetic field is removed.

The first permanent magnet unit 221 is located in a main area affected by the higher harmonic magnetic field, and the remanence induction intensity of the material is smaller, so that the eddy current loss generated in the first permanent magnet unit 221 is reduced.

It is understood that the first permanent magnet unit 221 and the second permanent magnet unit 222 are two permanent magnet units independent from each other.

The first permanent magnet unit 221 and the second permanent magnet unit 222 are bonded through an insulating layer 223, and the insulating layer 223 has insulativity and adhesiveness so as to realize the relative position fixation between the first permanent magnet unit 221 and the second permanent magnet unit 222.

It can be understood that dividing the permanent magnet 22 into two small permanent magnet units, the increase of the relative resistivity of the permanent magnet 22 reduces the eddy current of the permanent magnet 22, so that the loss generated by the eddy current of the permanent magnet 22 is reduced; the first permanent magnet unit 221 and the second permanent magnet unit 222 have different remanence induction intensities, so that the remanence induction intensity of a part of the permanent magnet 22, which is far away from the rotation axis of the rotor core 21 along the radial direction, is lower than that of other parts of the permanent magnet 22, thereby reducing eddy current loss of the part due to the influence of a higher harmonic magnetic field, further reducing the probability of occurrence of the problems of heating, demagnetization and the like of the permanent magnet 22 caused by the eddy current loss, and prolonging the service life of the rotor structure. Meanwhile, the residual magnetic induction intensity of the second permanent magnet unit 222 is higher, so that the overall magnetic induction intensity of the permanent magnet 22 is guaranteed to meet the power requirement of the motor. Eddy currents generated due to electromagnetic induction are reduced by the blocking effect of the insulating layer 223.

It is understood that the volume of the permanent magnet 22 may be equal to the volume of the space of the mounting groove 21 a; the space volume of the installation groove 21a may be smaller than that of the installation groove 21a, so that a magnetism isolating air groove can be formed between the permanent magnet 22 and the inner wall of the installation groove 21a, air is filled in the magnetism isolating air groove, and the magnetic permeability of the air is low and the magnetic resistance is high, so that the magnetic leakage is reduced.

The mounting groove 21a penetrates the rotor core 21 in the axial direction of the rotor core 21 so that the permanent magnet 22 is axially fitted into or removed from the mounting groove 21a.

In some embodiments, the first permanent magnet unit 221 is located at one end of the second permanent magnet unit 222 in the circumferential direction of the rotor core 21.

In some embodiments, the permanent magnet 22 includes two first permanent magnet units 221, one is located at one end of the second permanent magnet unit 222 away from the rotation axis along the circumferential direction of the rotor core 21, and the other is located at one end of the second permanent magnet unit 222 near the rotation axis along the circumferential direction of the rotor core 21, that is, both ends of the second permanent magnet unit 222 along the circumferential direction of the rotor core 21 are provided with the first permanent magnet units 221, so that in the assembly process link of loading the permanent magnet 22 into the mounting groove 21a, the mounting direction of the permanent magnet 22 does not need to be distinguished, the mounting efficiency is improved, and the probability of assembly errors is reduced.

The specific types of the material of the first permanent magnet unit 221 and the magnetic material of the second permanent magnet unit 222 are not limited, for example, samarium cobalt material, ferrite material, neodymium iron boron material, and the like, and the materials selected from the two materials can meet the requirement that the remanence induction intensity of the material of the first permanent magnet unit 221 is smaller than that of the material of the second permanent magnet unit 222

The magnetic energy product of the neodymium iron boron material is high, so that the size and the quality of the permanent magnet 22 are reduced on the basis of meeting the same magnetic induction intensity, and the energy density of the motor and the suitability of the motor are improved.

The first permanent magnet unit 221 and the second permanent magnet unit 222 are manufactured by different processes.

Illustratively, the first permanent magnet unit 221 is made of an adhesive neodymium-iron-boron material, and the second permanent magnet unit 222 is made of a sintered neodymium-iron-boron material.

The bonding NdFeB material is formed by mixing NdFeB powder and a bonding material, has strong shape plasticity, can be bonded and molded at one time through a die, is favorable for inhibiting eddy current loss generated by the influence of a higher harmonic magnetic field, reduces the waste of the material, and is convenient for the first permanent magnet unit 221 to be manufactured into different shapes according to requirements.

The sintered NdFeB material is prepared by pulverizing smelted NdFeB, pressing in a magnetic field, sintering and densifying the formed compact in inert gas or vacuum, and making the compact into a required shape by a machining mode without forming an additional insulating layer 223, thereby reducing material loss and improving material utilization rate.

Compared with the sintered neodymium-iron-boron material, the bonded neodymium-iron-boron material contains more other components and more air gaps, so that the remanence induction intensity of the bonded neodymium-iron-boron material is smaller than that of the sintered neodymium-iron-boron material, and the requirement that the remanence induction intensity of the material of the first permanent magnet unit 221 is smaller than that of the material of the second permanent magnet unit 222 is met.

In some embodiments, the magnetizing directions of the first permanent magnet unit 221 and the second permanent magnet unit 222 are the same, so as to reduce interference between the magnetic fields of the first permanent magnet unit 221 and the second permanent magnet unit 222.

It will be appreciated that the permanent magnet 22 has an N pole at one end in the magnetizing direction and an S pole at the other end.

In some embodiments, the radially inner side of rotor core 21 points radially outward in the magnetizing direction.

It should be noted that, in the direction perpendicular to the magnetizing direction, the size of the first permanent magnetic unit 221 and the size of the second permanent magnetic unit 222 are determined according to the required magnetomotive force, and the specific calculation method thereof is already applied in the related art and is not described herein.

It will be appreciated that the magnitude of the magnetic flux provided by the permanent magnet 22 per unit area is related to its size in the magnetizing direction.

In some embodiments, the size of the first permanent magnet unit 221 is smaller than the size of the second permanent magnet unit 222 in a direction perpendicular to the magnetizing direction. Since the remanence induction intensity of the material of the first permanent magnet unit 221 is smaller than the remanence induction intensity of the material of the second permanent magnet unit 222, increasing the ratio of the size of the second permanent magnet unit 222 to the total size of the permanent magnet 22 in the direction perpendicular to the magnetizing direction is beneficial to increasing the total magnetic flux of the permanent magnet 22, and to reducing the total size of the permanent magnet 22 while meeting the requirement of the total magnetic flux of the permanent magnet 22.

In some embodiments, referring to fig. 15, an end surface of a side of the first permanent magnet unit 221, which is far away from the rotation axis along the magnetizing direction, is a first end surface 221a, an end surface of a side of the second permanent magnet unit 222, which is far away from the rotation axis along the magnetizing direction, is a second end surface 222a, and the second end surface 222a is flush with the first end surface 221a along the magnetizing direction, so as to reduce an area of the first permanent magnet unit 221 affected by the higher harmonic magnetic field, reduce eddy current loss in the permanent magnet 22, and reduce heat generation of the permanent magnet 22 during operation.

In some embodiments, the second end surface 222a exceeds the first end surface 221a along the magnetizing direction, that is, the end of the permanent magnet 22 far from the rotation axis along the radial direction of the rotor core 21 is free, so as to improve the magnetic potential of the end of the second permanent magnet unit 222 far from the rotation axis, and improve the anti-demagnetizing capability of the second permanent magnet unit 222; and reduces the area of the first permanent magnet unit 221 affected by the higher harmonic magnetic field, so as to further reduce eddy current loss in the permanent magnet 22 and reduce heat generation of the permanent magnet 22 in the working process.

In some embodiments, the second end surface 222a exceeds the first end surface 221a along the magnetizing direction, that is, the end of the permanent magnet 22 far from the rotation axis along the radial direction of the rotor core 21 is free, so as to improve the magnetic potential of the end of the second permanent magnet unit 222 far from the rotation axis, and improve the anti-demagnetizing capability of the second permanent magnet unit 222; and reduces the area of the first permanent magnet unit 221 affected by the higher harmonic magnetic field, so as to further reduce eddy current loss in the permanent magnet 22 and reduce heat generation of the permanent magnet 22 in the working process.

In some embodiments, the dimension of the first permanent magnet unit 221 along the magnetizing direction is not greater than the dimension of the second permanent magnet unit 222 along the magnetizing direction, so as to reduce the area of the first permanent magnet unit 221 affected by the higher harmonic magnetic field, reduce eddy current loss in the permanent magnet 22, and reduce the heat generation of the permanent magnet 22 during the working process.

Illustratively, the mounting grooves 21a are arranged in pairs, a spacing cavity 21b is arranged between one ends, close to the rotation axis, of at least part of the two mounting grooves 21a in pairs, and a non-magnetic block 23 is arranged in the spacing cavity 21b, so that the permanent magnetic circuit of eddy current is reduced, and the heating value is further reduced.

In some embodiments, the number of the mounting slots 21a is multiple, each pair of mounting slots 21a is arranged at intervals along the circumferential direction of the rotor core 21 and is symmetrical along the radial direction, and the distance between the two mounting slots 21a in each pair is gradually increased from inside to outside along the radial direction of the rotor core 21, so that the radial magnetic flux leakage of the permanent magnet 22 is reduced, the utilization rate of the magnetic flux of the permanent magnet 22 is improved, and the increase of the air gap density of the motor is facilitated.

The specific arrangement of each pair of the mounting grooves 21a is not limited, and is, for example, V-shaped or U-shaped.

In the description of the present application, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the embodiments of the present application. In this application, the schematic representations of the above terms are not necessarily for the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the various embodiments or examples described herein, as well as the features of the various embodiments or examples, may be combined by those skilled in the art without contradiction.

The foregoing description is only of the preferred embodiments of the present application and is not intended to limit the same, but rather, various modifications and variations can be made by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims (21)

1. An electric machine, the electric machine comprising:

the shell assembly is provided with bearing chambers at two axial ends;

a rotor assembly disposed within the housing assembly, the rotor assembly including a rotor core;

and the two first heat insulation pieces are respectively arranged outside the bearing chambers and used for isolating heat exchange between the rotor core and the bearing chambers.

2. The motor of claim 1, wherein the first insulation member is disposed around the bearing housing outer sidewall and cooperates with the bearing housing outer sidewall to define a first air path.

3. A motor as claimed in claim 2, wherein a second air passage is formed in the rotor assembly, the second air passage being in communication with the first air passage, the housing assembly being provided with an air inlet and an air outlet, the air inlet being in communication with one of the first air passages, the air outlet being in communication with the other of the first air passages.

4. The motor of claim 2, wherein the housing assembly defines a boss surrounding the bearing chamber to one side of the first heat shield, and wherein the first heat shield is disposed outside the boss and is in clearance fit with the boss.

5. The electric machine of claim 1, including a stator assembly disposed between the housing assembly and the rotor assembly and a second thermal shield disposed between the stator assembly and the rotor assembly for isolating heat exchange between the stator assembly and the rotor assembly.

6. The electric machine of claim 5, wherein the second insulation comprises insulation coating on an inner surface of the stator assembly.

7. The electric machine of claim 5 wherein the stator assembly includes a stator core and stator windings, the stator winding portions extending from axial ends of the stator core to form end windings;

the second heat insulator includes a heat insulating cylinder provided inside the end winding to insulate the end winding from heat exchange with the bearing chamber.

8. The electric machine of claim 7 wherein the insulation cartridge is sealingly connected between the housing assembly and the stator assembly.

9. The motor of claim 7, wherein the rotor assembly defines a cavity with the heat shield, the first heat shield, and the housing assembly at both axial ends thereof, and wherein the rotor assembly defines a through hole therein, the through hole communicating with the cavity to collectively form the circulation duct.

10. The motor of claim 9, wherein two of said first heat shields are coupled to said rotor assembly, and wherein fan blades are formed on an outer sidewall of at least one of said first heat shields.

11. An electric machine as claimed in claim 1, characterized in that the electric machine comprises a stator assembly comprising a stator core and stator windings, the stator winding parts protruding from both axial ends of the stator core to form end windings, the wires of the end windings having gaps therebetween, and a heat-conducting member at least partially filling the gaps of the end windings.

12. The electric machine according to claim 11, wherein the heat conducting member includes a sleeve and a first heat conducting filling portion, the sleeve being fitted over the outer side of the end winding, the first heat conducting filling portion being filled in a gap of the end winding and between the end winding and the sleeve;

wherein the thermal conductivity of the material of the sleeve is greater than the thermal conductivity of the material of the first thermally conductive filler.

13. The electric machine of claim 12, wherein the sleeve includes a sleeve body and a set of heat dissipating fins protruding from an outer peripheral surface of the sleeve body.

14. The electric machine of claim 13, wherein the housing assembly and the stator core define a third air path therebetween, and wherein the set of heat dissipating fins is disposed within the third air path.

15. The electric machine of claim 12, wherein the sleeve includes a sleeve body and a plurality of inwardly projecting heat conductive ribs disposed on the sleeve body, each of the heat conductive ribs being circumferentially spaced along the sleeve body.

16. An electric machine as claimed in claim 1, wherein the rotor assembly comprises

A rotor core provided with an installation groove therein;

the permanent magnet is arranged in the mounting groove and comprises a first permanent magnet unit and a second permanent magnet unit, the first permanent magnet unit is positioned at one end, far away from the rotation axis, of the second permanent magnet unit along the radial direction of the rotor core, the residual magnetic induction intensity of the material of the first permanent magnet unit is smaller than that of the material of the second permanent magnet unit, and the first permanent magnet unit and the second permanent magnet unit are bonded through an insulating layer.

17. The motor of claim 16, wherein the first permanent magnet unit is bonded neodymium-iron-boron material and the second permanent magnet unit is sintered neodymium-iron-boron material.

18. The electric machine of claim 16, wherein the first permanent magnet unit and the second permanent magnet unit are magnetized in the same direction.

19. The electric machine of claim 18, wherein the first permanent magnet unit has a smaller size than the second permanent magnet unit in a direction perpendicular to the magnetizing direction.

20. The electric machine of claim 18, wherein an end surface of the first permanent magnet unit on a side away from the rotation axis in the magnetizing direction is a first end surface, and an end surface of the second permanent magnet unit on a side away from the rotation axis in the magnetizing direction is a second end surface, the second end surface being beyond or flush with the first end surface in the magnetizing direction.

21. An electric machine as claimed in claim 16, characterized in that the mounting grooves are arranged in pairs, at least some of the two mounting grooves in pairs having a compartment between their ends adjacent the axis of rotation, the compartment being provided with non-magnetic blocks.