CN111600403A

CN111600403A - Outer rotor permanent magnet motor

Info

Publication number: CN111600403A
Application number: CN202010534288.6A
Authority: CN
Inventors: 钟正平; 钟广财
Original assignee: Zhejiang Kesheng Machinery Electrical Co ltd
Current assignee: Zhejiang Kesheng Machinery Electrical Co ltd
Priority date: 2020-06-11
Filing date: 2020-06-11
Publication date: 2020-08-28

Abstract

The invention discloses an outer rotor permanent magnet motor, and belongs to the technical field of motors. The stator assembly comprises a main shaft, a stator assembly is fixed on the main shaft, the stator assembly comprises a stator support, an enameled coil is arranged outside the stator support, the main shaft penetrates through a center hole of the stator support, an outer rotor is sleeved outside the stator assembly, the stator assembly is packaged through an upper cover and a lower cover, the main shaft penetrates through the upper cover and the center hole of the lower cover, the upper cover and the lower cover rotate through a first bearing and a second bearing respectively, a plurality of cooling cavities are formed in the bottom surface of the stator support, an inner bearing support is fixed at the lower end of the main shaft, a gas channel is arranged in the inner bearing support, a plurality of vane plates extending from inside to outside are formed on the bottom surface of the lower cover, a drainage cover is arranged on the lower side of the lower cover, a heat dissipation cavity is formed between the drainage cover and the lower cover, air inlets communicated with the gas channel and the heat dissipation cavity are formed in. The invention has the advantages of obvious heat dissipation effect, prolonged service life of the motor and the like.

Description

Outer rotor permanent magnet motor

Technical Field

The invention belongs to the technical field of motors, and particularly relates to an outer rotor permanent magnet motor.

Background

At present, a traditional outer rotor permanent magnet motor is a closed space formed by buckling an upper cover and a lower cover of a rotor, and a stator is arranged in the closed space. After the rotor works for a long time, an enameled coil in the motor can generate a large amount of heat, and due to the closed structure of the permanent magnet motor, heat energy cannot be dissipated timely, so that the magnetic steel and the enameled coil in the permanent magnet motor are greatly damaged, and the service life of the outer rotor permanent magnet motor is short.

With the development of times and the progress of science and technology, the outer rotor permanent magnet motor with the water-cooling heat conduction structure arranged in the main shaft appears in the market, and the water-cooling heat conduction structure in the structure is only contacted with the part at the joint of the main shaft and the stator, and the position between the rotor and the stator, namely the position of an enameled coil, is the main heating position, so that the heat dissipation position is not accurate enough, and the heat dissipation effect is poor.

Disclosure of Invention

The invention aims to provide an outer rotor permanent magnet motor, which can reduce the temperature generated when the motor works, improve the heat dissipation capability and further prolong the service life of the outer rotor permanent magnet motor.

The purpose of the invention is realized as follows:

an outer rotor permanent magnet motor comprises a main shaft, a stator group is fixed on the main shaft, the stator group comprises a stator support, an enameled coil is arranged outside the stator support, the main shaft penetrates through a middle hole of the stator support, an outer rotor is sleeved outside the stator group, the stator group is packaged by an upper cover and a lower cover which are fixedly connected with the upper end and the lower end of the outer rotor, the main shaft penetrates through the middle holes of the upper cover and the lower cover, the upper cover and the lower cover rotate through a first bearing and a second bearing which are fixed on the main shaft respectively, a plurality of cooling cavities are formed in the bottom surface of the stator support, an inner bearing support for fixing a second bearing is fixed at the lower end of the main shaft, an air channel communicated with the cooling cavities is arranged in the inner bearing support, a plurality of vane plates extending from inside to outside are formed in the bottom surface of the lower cover, and a drainage cover fixed at the bottom of, a heat dissipation cavity is formed between the drainage cover and the lower cover, an air inlet hole communicated with the air channel and the heat dissipation cavity is formed in the drainage cover, and a plurality of air outlets are formed in the outer side of the drainage cover and the air vane plate.

The invention is further arranged in such a way that the upper end of the bearing inner support is provided with an annular sealing sheet, the upper end surface of the annular sealing sheet is abutted against the lower end surface of the stator support, and the inner circle of the annular sealing sheet is used for communicating the cooling cavity with the gas channel.

The invention is further arranged in such a way that the lower end of the inner support of the bearing is provided with an oil seal, the outer ring of the oil seal is abutted against the inner ring of the middle hole of the lower cover, and the inner ring of the oil seal is fixed by a bushing arranged at the lower end of the inner support of the bearing.

The invention is further arranged such that the air inlet is arranged directly below the air channel.

The invention is further arranged in such a way that an air inlet groove protruding upwards is formed in the center of the bottom of the drainage cover, the air inlet groove is of a cylindrical groove structure, and the air inlet hole is formed in the bottom of the air inlet groove.

The invention is further arranged that the upper cover and the lower cover are fixed with the outer rotor by means of bolts.

The invention is further arranged that the support in the bearing is fixed with the main shaft by a pin key.

Compared with the prior art, the invention has the outstanding and beneficial technical effects that:

1. according to the invention, the stator support on the main shaft is additionally provided with the cooling cavity communicated with the outside air, the lower cover connected with the lower end of the outer rotor rotates along with the outer rotor, the gas in the heat dissipation cavity flows out through the air outlet by utilizing the centrifugal force generated in the rotation process of the plurality of fan blades, and the air inlet formed on the drainage cover can continuously intake air by utilizing the generated air pressure, so that the efficient air exchange of the cooling cavity in the stator support is realized, the heat dissipation efficiency is greatly improved, and the service life of the outer rotor permanent magnet motor is ensured.

2. The annular sealing sheet is adopted, so that air and the inside of the motor, namely an enameled coil on the stator can be blocked from the outside, the cooling cavity in the stator support can be ensured to be communicated with a gas channel, and the inner walls of the enameled coil and the outer rotor in the motor are prevented from being affected with damp and corroded.

3. The invention adopts the oil seal to seal the joint, further enhances the sealing property inside the motor, and simultaneously ensures that the external air and the dust in the external air can not enter the joint between the lower cover and the bearing inner bracket from the gas channel in the rotating process of the outer rotor.

4. The air inlet holes are arranged right below the gas channel, so that the air is easy to firstly flow into the gas channel when air is fed, and the cooling cavity communicated with the gas channel can also firstly flow into the gas channel, so that the temperature is reduced, and the better heat dissipation efficiency is realized.

5. According to the invention, the center of the bottom of the flow guide cover is arranged to be the cylindrical groove structure, so that gas can not be disordered when gas is fed and gas is discharged from the side edge, the high-efficiency circulation of the gas in the motor is realized, and a better heat dissipation effect is achieved.

Drawings

FIG. 1 is a schematic cross-sectional view of the present invention;

FIG. 2 is an exploded schematic view of the present invention;

FIG. 3 is a schematic perspective view of the structure of the present invention;

FIG. 4 is a schematic view of the construction of the drainage mask of the present invention;

FIG. 5 is a schematic view of the construction of the lower cover of the present invention;

FIG. 6 is a schematic view of the pin key of the present invention positioned on the spindle;

FIG. 7 is an enlarged schematic view of detail A of FIG. 1;

FIG. 8 is an enlarged schematic view of portion B of FIG. 1

FIG. 9 is a schematic view of the gas flow space structure of the present invention;

FIG. 10 is a sectional perspective view of the stator inner frame according to the second embodiment of the present invention;

reference numerals:

1-a main shaft; 10-a first bearing; 11-a second bearing; 12-pin key; 13-a power line;

2-stator group; 20-a stator support; 200-cooling the cavity; 21-enameled coil;

3-an outer rotor; 4, covering the upper cover; 5-lower cover; 50-a vane plate; 51-a heat dissipation cavity;

6-inner bearing support; 60-gas channels; 7-a drainage cover; 70-air intake; 71-air outlet;

72-an air intake recess; 8-ring-shaped sealing piece; 9-oil sealing; 90-bushing.

Detailed Description

The invention will be further described in the following with reference to specific embodiments thereof, with reference to the accompanying drawings, in which figures 1 to 9:

the first embodiment is as follows:

an outer rotor permanent magnet motor comprises a main shaft 1, a stator group 2 is fixed on the main shaft 1, the stator group 2 comprises a stator support 20, an enameled coil 21 is arranged outside the stator support 20, the main shaft 1 penetrates through a middle hole of the stator support 20, an outer rotor 3 is sleeved outside the stator group 2, the stator group 2 is packaged by an upper cover 4 and a lower cover 5 which are fixedly connected with the upper end and the lower end of the outer rotor 3, the stator group is wrapped inside by the upper cover 4 and the lower cover 5 which are buckled with each other, the outer rotor 3, the upper cover 4 and the lower cover 5 rotate simultaneously, the main shaft 1 penetrates through middle holes of the upper cover 4 and the lower cover 5, the upper cover 4 and the lower cover 5 rotate through a first bearing 10 and a second bearing 11 which are fixed on the main shaft 1 respectively, the first bearing 10 and the second bearing 11 can reduce friction between the upper cover 4 and the lower cover 5 and the main shaft 1, a plurality of cooling cavities 200 are formed in the bottom surface of the, an inner bearing support 6 for mounting a second bearing 11 is fixed at the lower end of the main shaft 1, an air channel 60 communicated with the cooling cavity 200 is arranged in the inner bearing support 6, a plurality of vane plates 50 extending from inside to outside are formed on the bottom surface of the lower cover 5, a flow guide cover 7 fixed at the bottom of the main shaft 1 is arranged on the lower side of the lower cover 5, a heat dissipation cavity 51 is formed between the flow guide cover 7 and the lower cover 5, an air inlet 70 communicated with the air channel 60 and the heat dissipation cavity 51 is formed in the flow guide cover 7, and a plurality of air outlets 71 are formed between the outer side of the flow guide cover 7 and the adjacent vane plates 50.

The heat dissipation principle is as follows: as shown in fig. 9, when the lower cover 5 rotates along with the outer rotor 3, the bottom vane plate 50 rotates together, at this time, the air and heat in the heat dissipation cavity 51 are continuously thrown out to the air outlet 71 by the centrifugal force provided by the continuous rotation of the vane plate 50, the air channel 60, the cooling cavity 200 and the air inlet 70 communicated with the heat dissipation cavity 51 achieve the balance of air pressure and heat energy, the air inlet 70 continuously admits air, the heat energy of the cooling cavity 200 is continuously conducted to the heat dissipation cavity 51, so as to achieve the purpose of achieving a good heat dissipation effect by rotating the outer rotor 3, and the flowing range and direction of the air are marked by thick lines in fig. 9.

It should be mentioned that, as shown in fig. 1 and fig. 6, a through hole for placing a power line is formed in the main shaft 1, a lead-out hole for leading out the power line 13 is provided on the main shaft 1, the power line 13 is connected with the enameled coil 21, the enameled coil 21 after being powered on can drive the outer rotor 3 to rotate, and the principle of the magnetic field driven by the powered coil is not repeated.

In addition, the above-mentioned vane plate 50 is preferably selected as a vane structure having a stronger wind force when the outer rotor 3 drives the lower cover 5 to rotate, and in this embodiment, a structure similar to a straight plate is preferably used as the vane plate 50, so that the heat energy and the gas in the heat dissipation cavity 51 can be more directly thrown out, and the heat dissipation is more efficient.

Preferably, as shown in fig. 1 and 8, an annular sealing sheet 8 is disposed at the upper end of the bearing inner support 6, the upper end surface of the annular sealing sheet 8 abuts against the lower end surface of the stator support 20, and the inner circle of the annular sealing sheet 8 communicates the cooling cavity 200 with the gas channel 60, since the vane plate 50 disposed at the lower end of the lower cover 5 has a longer length, it can be ensured that heat energy and gas efficiently flow out from the air outlet 71, and the purpose of heat dissipation is achieved, and the space required by the enameled coil 21 on the stator and the adapted outer rotor 3 is only a slightly larger space of the outer ring of the motor inner stator support 20, so that the lower cover 5 cannot adopt a smaller outer ring size only for adapting to the required space. And the lower cover with a larger radius is used for ensuring the sufficient length of the wind vane plate 50, and the position of the middle hole of the lower cover 5 can be simultaneously used for installing the bearing inner support 6, and communicates with the cooling cavity 200, the upper end of the second bearing 11 is necessarily in contact with the cooling cavity 200, and the added ring-shaped sealing sheet 8 can effectively block the upper surface of the second bearing 11 from contacting with the cooling cavity 200, and the inner ring of the ring can simultaneously ensure that the cooling cavity 200 is communicated with the gas channel in the bearing inner support 6, this annular sealing fin 8 effectively blocks the inside and external contact of motor, can prevent that the air from getting into second bearing 11 from cooling cavity 200 and also can place its entering motor enamelled coil 21 department, effectively prevents that inside from weing, gets into the dust, has ensured this external rotor electric machine's life, has replaced on the market to utilize directly to punch at upper cover or lower cover and dispel heat outer rotor electric machine such as.

Preferably, as shown in fig. 7, an oil seal 9 is disposed at the lower end of the bearing inner support 6, an outer ring of the oil seal 9 abuts against an inner ring of a center hole of the lower cover 5, an inner ring of the oil seal 9 is fixed by a bushing 90 disposed at the lower end of the bearing inner support 6, in order to block gas from entering from a gap between the center hole of the lower cover 5 and the bottom of the stator support 20, the connection is an irregular gap structure, the bushing 90 is used to seal longitudinally, and then the oil seal 9 is used to seal transversely, so that the connection effectively blocks gas from entering.

The structure of the oil seal 9 is also suitable for connection between the hole position of the upper cover 4 and the main shaft 1, effectively prevents gas from gushing from the first bearing 10 of the upper cover 4, and prevents the interior of the outer rotor motor from being damped.

Preferably, the air inlet holes 70 are arranged right below the air channel 60, the positions of the air inlet holes 70 can be arranged at any position on the flow guide cover 7, but the air inlet holes 70 are preferably arranged right below the air channel 60, so that air from the air inlet holes 70, namely air with lower temperature than that in the cooling cavity 200, can be preferentially gushed into the cooling cavity to realize cooling and heat dissipation, and the air inlet holes are arranged at other positions, so that the heat dissipation is preferentially aimed at the position of the heat dissipation cavity 51, and the stator support cannot obtain too much heat dissipation, thereby causing poor heat dissipation effect.

Preferably, as shown in fig. 2 and 4, an air inlet groove 72 protruding upwards is formed in the center of the bottom of the flow guide cover 7, the air inlet groove 72 is in a cylindrical groove structure, and the air inlet holes 70 are disposed at the bottom of the air inlet groove 72.

The above structure further enables the air inlet holes 70 to act more directly on the lower contact portion of the air channel 60, so that the heat dissipation effect is more excellent.

It should be noted that, because the stator support 20 and the bearing inner support 6 are always in a static state in the working state of the motor, the number of cooling cavities formed in the stator support 20 is preferably the same as the number of gas channels formed in the bearing inner support 6, and the cooling cavities are in one-to-one correspondence, so that the heat dissipation effect is more efficient, and in addition, the air inlets 70 are preferably uniformly distributed at all positions of the bottom of the air inlet groove 72, which can be set, so that the heat dissipation maximization is realized.

Preferably, the upper cover 4 and the lower cover 5 are fixed with the outer rotor 3 in a bolt manner, the split structure facilitates the installation and the disassembly of the outer rotor motor, in addition, the upper cover 4 and the outer rotor 3 can be an integrated structure or the lower cover 5 and the outer rotor 3 can be an integrated structure, and the three structures can realize the upper and lower sealing of the motor.

Preferably, as shown in fig. 6, the bearing inner support 6 is fixed with the main shaft 1 through a pin key 12, and the pin key 12 may be a flat key or a semicircular key, so as to enhance the fixing effect of the bearing inner support 6 with the main shaft 1.

Example two:

the present embodiment is similar to the embodiment, except that, as shown in fig. 10, the bearing inner bracket 6 is provided with guide fins which make the bearing inner bracket 6 form concentric rings with different sizes, wherein the inner ring corresponds to the air inlet 70 and the cooling cavity 200, and the outer ring corresponds to the cooling cavity 200 and the heat dissipation cavity 51, which can make the air flow without confusion.

It is worth mentioning that for optimal gas flow, the above-mentioned guiding fins should preferably be arranged at the center of the intersection of the gas channel 60 and the cooling cavity 200.

The working principle is as follows:

according to the invention, the air vane plate 50 arranged on the lower cover 5 fixedly connected with the outer rotor 3 is utilized, in the rotating process, the air outlet 71 formed between the air vane plate and the flow guide cover 7 can discharge heat and gas in the heat dissipation cavity 51, the gas channel 60 and the cooling cavity 200 in the stator support 20, the air inlet 70 arranged on the flow guide cover 7 is utilized to realize air pressure balance, continuous heat dissipation of the stator support 20 is realized along with continuous inflow of the gas in the rotating process, and therefore the enameled coil 21 arranged on the outer side of the stator support 20 can dissipate heat in time; in addition, the oil seal 9, the bushing 90 and other structures play a good separation effect on the connection part of the air inlet, so that the inner part of the outer rotor permanent magnet motor cannot be damaged due to dust or water vapor gushed from the air, and the service life of the outer rotor permanent magnet motor is guaranteed.

The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.

Claims

1. The outer rotor permanent magnet motor is characterized by comprising a main shaft (1), a stator group (2) is fixed on the main shaft (1), the stator group (2) comprises a stator support (20), an enameled coil (21) is arranged outside the stator support (20), the main shaft (1) penetrates through a center hole of the stator support (20), an outer rotor (3) is sleeved outside the stator group (2), the stator group (2) is packaged by an upper cover (4) and a lower cover (5) which are fixedly connected with the upper end and the lower end of the outer rotor (3), the main shaft (1) penetrates through the center holes of the upper cover (4) and the lower cover (5), the upper cover (4) and the lower cover (5) rotate through a first bearing (10) and a second bearing (11) which are fixed on the main shaft (1), a plurality of cooling cavities (200) are formed in the bottom surface of the stator support (20), the air cooling device is characterized in that a bearing inner support (6) used for mounting a second bearing (11) is fixed at the lower end of the main shaft (1), a gas channel (60) communicated with the cooling cavity (200) is arranged in the bearing inner support (6), a plurality of fan blades (50) extending from inside to outside are formed on the bottom surface of the lower cover (5), a drainage cover (7) fixed at the bottom of the main shaft (1) is arranged on the lower side of the lower cover (5), a heat dissipation cavity (51) is formed between the drainage cover (7) and the lower cover (5), air inlets (70) communicated with the gas channel (60) and the heat dissipation cavity (51) are formed in the drainage cover (7), and a plurality of air outlets (71) are formed between the outer side of the drainage cover (7) and the adjacent fan blades (50).

2. The outer rotor permanent magnet motor according to claim 1, wherein an upper end of the inner bearing support (6) is provided with an annular sealing sheet (8), an upper end face of the annular sealing sheet (8) is abutted against a lower end face of the stator support (20), and an inner circle of the annular sealing sheet (8) is used for communicating the cooling cavity (200) with the gas channel (60).

3. The outer rotor permanent magnet motor according to claim 1 or 2, wherein an oil seal (9) is arranged at the lower end of the inner bearing support (6), the outer ring of the oil seal (9) abuts against the inner ring of the middle hole of the lower cover (5), and the inner ring of the oil seal (9) is fixed by a bushing (90) arranged at the lower end of the inner bearing support (6).

4. The external rotor permanent magnet motor according to claim 1, wherein the air inlet holes (70) are arranged right below the air channel (60).

5. The outer rotor permanent magnet motor according to claim 4, wherein an air inlet groove (72) protruding upwards is formed in the center of the bottom of the flow guide cover (7), the air inlet groove (72) is of a cylindrical groove structure, and the air inlet holes (70) are formed in the bottom of the air inlet groove (72).

6. The external rotor permanent magnet machine according to claim 1, wherein the upper cover (4) and the lower cover (5) are fixed to the external rotor (3) by means of bolts.

7. The external rotor permanent magnet motor according to claim 1, wherein the bearing inner support (6) is fixed with the main shaft (1) through a pin key (12).