CN111478472A

CN111478472A - Rotor structure and motor and air compressor adopting same

Info

Publication number: CN111478472A
Application number: CN202010430349.4A
Authority: CN
Inventors: 华青松; 刘亚波; 邱瑞林; 王素景
Original assignee: Beijing Wenli Tech Co ltd
Current assignee: Beijing Wenli Tech Co ltd
Priority date: 2020-05-20
Filing date: 2020-05-20
Publication date: 2020-07-31

Abstract

The invention discloses a rotor structure and a motor and an air compressor adopting the same, wherein the rotor structure comprises a sheath and a permanent magnet arranged in the sheath, the sheaths on the outer sides of two ends of the permanent magnet form insertion parts, mandrels on two sides are respectively inserted and fixed in the insertion parts on two sides of the sheath, and the mandrels are of a hollow structure; the bottom wall of the mandrel, which is opposite to the permanent magnet, is provided with a first through hole, and the side wall of the mandrel, which is positioned outside the sheath, is provided with a second through hole. By the adoption of the scheme, the rotor structure is optimized, the weight of the rotor can be greatly reduced on the basis of meeting the normal use function, and a good technical guarantee is provided for meeting the design requirement of the lightweight rotor.

Description

Rotor structure and motor and air compressor adopting same

Technical Field

The invention relates to the technical field of rotor structure design, in particular to a rotor structure and a motor and an air compressor adopting the rotor structure.

Background

As is well known, a motor is composed of a rotor and a stator, and the conversion between electric energy and mechanical energy is realized according to the faraday's law of electromagnetic induction by a winding coil on the stator and a permanent magnet on the rotor. Wherein, the rotor is the rotating part in the motor. Generally, a motor with a rotating speed of more than 10000r/min is defined as a high-speed motor.

Referring now to FIG. 5, a high speed rotor shaft of the prior art is shown. As shown, the rotor thereof is composed of a magnetic core 12, a sleeve 14, a nonmagnetic boss 16, a magnetic boss 18, a spacer 17, and a magnetic bearing 19. In assembly, the sleeve 14 is heated by a heater, and then the core 12, the nonmagnetic coupling 16, the spacer 17, and the magnetic coupling 18 are inserted by a shaking tool. After the sleeve is rapidly cooled, so that the sleeve 14 shrinks around the outer surfaces of the non-magnetic boss 16, the magnetic boss 18, the sleeve 14 and the core 12, placing the spacer 17 and the core 12 in compression. In the scheme, the non-magnetic shaft coupling 16 and the magnetic shaft coupling 18 are both of a solid structure, the rotor has large mass, and the bearing needs to bear heavy weight, so that the energy efficiency of the motor is influenced.

Please refer to fig. 6, which is a schematic view of a shafting structure of another typical motor in the prior art. As shown in the figure, the rotor of the magnetic steel rotor consists of a front section shaft 62, a rear section shaft 63, annular magnetic steel 61 and an alloy sheath 60. The front end shaft 62 and the rear end shaft 63 are also of solid structures, and the defect of high rotor mass is also caused.

In view of the above, it is desirable to optimize the rotor structure of the existing motor to effectively control the rotor quality.

Disclosure of Invention

In order to solve the technical problems, the invention provides a rotor structure and a motor and an air compressor adopting the rotor structure, and the rotor structure is optimized, so that the weight of the rotor can be greatly reduced on the basis of meeting the normal use function, and a good technical guarantee is provided for meeting the design requirement of a lightweight rotor.

The rotor structure comprises a sheath and a permanent magnet arranged in the sheath, wherein the sheath on the outer sides of two ends of the permanent magnet forms an inserting part, mandrels on two sides are respectively inserted and fixed in the inserting parts on two sides of the sheath, and the mandrels are of a hollow structure; the bottom wall of the mandrel, which is opposite to the permanent magnet, is provided with a first through hole, and the side wall of the mandrel, which is positioned outside the sheath, is provided with a second through hole.

Preferably, the mandrel comprises a mandrel body and an adaptor; the mandrel body is integrally cylindrical, an opening is formed in one end of the mandrel body, the bottom side of the mandrel body is fixedly inserted into the insertion part on the corresponding side, and the first through hole is formed in the bottom of the mandrel body; the adapter body is connected with the opening of the mandrel body in a sealing mode to form the hollow structure, and the second through hole is formed in the side wall of the adapter body and/or the side wall of the mandrel body.

Preferably, the first through holes are arranged at one axial center position or are arranged in a plurality of circumferentially and uniformly distributed positions; the second through holes are circumferentially and uniformly distributed.

Preferably, the rotor structure is a two-stage rotor, and the matching bodies of the mandrels on two sides are both provided with wheel shafts which are formed by axial outward extension and used for installing impellers; a sealing disc is fixedly arranged on the wheel shaft on the inner side of the impeller and used for forming a sealing pair with a sealing channel on a motor end cover; and a thrust disc is fixedly arranged on one wheel shaft and is positioned on the inner side of the sealing disc.

Preferably, the rotor structure is a single-stage rotor, and the adapter body of the mandrel on one side is provided with an axially outwards-extending formed wheel shaft for installing an impeller; a sealing disc is fixedly arranged on the wheel shaft on the inner side of the impeller and used for forming a sealing pair with a sealing channel on a motor end cover, a thrust disc is fixedly arranged on the wheel shaft and is positioned on the inner side of the sealing disc; the adapter body of the mandrel on the other side is a cover body.

Preferably, the adapter body on the inner side of the wheel shaft is provided with a cylindrical connecting part inserted and matched with the mandrel body, and the outer end part of the wheel shaft is provided with a threaded section matched with a nut so as to lock the impeller arranged on the corresponding wheel shaft.

Preferably, the mandrel body and the inserting portion are fixed in an interference fit and/or a welding manner, and the adapter and the mandrel body are fixed in an interference fit and/or a welding manner.

Preferably, the material of the sheath and the mandrel body is a non-magnetic material; the permanent magnet is made of rare earth neodymium iron boron or rare earth samarium cobalt, is cylindrical or annular, and is magnetized in parallel along the radius direction of the cylinder or the ring respectively.

The invention also provides a motor which comprises a rotor and a stator which are matched, wherein the rotor adopts the rotor structure.

The invention also provides an air compressor which comprises the motor.

For the rotor with the existing solid structure, the invention provides structural improvement and optimization. Specifically, the permanent magnet is arranged in the sheath, and the sheaths on the outer sides of the two ends of the permanent magnet form inserting parts which are respectively used for inserting the mandrels on the two sides; a first through hole is formed in the bottom wall of the mandrel, which is opposite to the permanent magnet, and a second through hole is formed in the side wall of the mandrel, which is located on the outer side of the inserting portion. Compared with the prior art, the invention has the following beneficial technical effects:

firstly, based on hollow structure design dabber, but greatly reduced rotor weight to reduce bearing load, accord with the design demand of product lightweight. Meanwhile, the hollow mandrel is fixedly inserted into the inserting parts at the two ends of the permanent magnet, so that the assembly operation is convenient, the connection reliability of the main body bearing structure can be ensured, a first through hole is formed in the bottom wall of the mandrel, which is opposite to the permanent magnet, and a second through hole is formed in the side wall of the mandrel, which is positioned outside the sheath; so set up, when the dabber was assembled, can establish the regional air escape channel between dabber and the permanent magnet, the zero clearance equipment of complete butt can be realized between the two, reduces axial assembly error, has better assembly manufacturability.

And secondly, based on the arrangement of the second through hole on the mandrel, in the running process of the motor or the air compressor, the gas expanded by heat in the hollow structure can be effectively removed, the mandrel can be prevented from bearing larger gas pressure, and the safety and reliability of the running of the motor or the air pressure can be further improved.

Thirdly, in a preferred scheme of the invention, the mandrel comprises a mandrel body and an adapter body which are sealed and connected to form the hollow structure; the cylinder bottom side of the cylindrical mandrel body is fixedly inserted in the inserting part, the first through hole is formed in the cylinder bottom of the mandrel body, and correspondingly, the second through hole is formed in the side wall of the adapter and/or the mandrel body. So set up, adopt split type structural design, easily machine-shaping, specific better processing technology nature, but greatly reduced product manufacturing cost.

Drawings

FIG. 1 is a schematic view of an assembly of the rotor structure according to one embodiment;

FIG. 2 is a schematic view of the overall structure of the mandrel body;

FIG. 3 is a schematic diagram showing the overall structure of the aptamer;

FIG. 4 is an assembly view of the rotor structure according to the second embodiment;

FIG. 5 is a schematic view of a typical high speed rotor shaft of the prior art;

fig. 6 is a schematic view of a shafting structure of another typical motor.

In the figure:

the outer sleeve comprises a jacket 1, an insertion part 11, a permanent magnet 2, a first impeller 31, a second impeller 32, a first mandrel 41, a first mandrel body 411, a first adapter 412, a first wheel shaft 4121, a first connecting part 4122, a second mandrel 42, a second mandrel body 421, a second adapter 422, a second wheel shaft 4221, a second connecting part 4222, a first through hole 43, a second through hole 44, a first sealing disc 51, a second sealing disc 52, a thrust disc 6, a first nut 71, a second nut 72, a mandrel 8, a mandrel body 81 and an adapter 82.

Detailed Description

In order to make the technical solutions of the present invention better understood by those skilled in the art, the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments.

Without loss of generality, the embodiment takes the rotor shown in the figure as a description basis, and details an innovative scheme aiming at the rotor structure. It should be understood that the impeller disposed at the end of the rotor shaft in the figures is not the core inventive point of the present application and does not constitute a substantial limitation on the rotor structure claimed herein.

The first embodiment is as follows:

referring to fig. 1, there is shown an assembly view of the rotor structure according to the present embodiment, in which the two-stage rotor is applicable to a two-stage type impeller air compressor. The rotor structure comprises a sheath 1, a permanent magnet 2 and mandrels (41, 42) on both sides for mounting impellers (31, 32).

Wherein, permanent magnet 2 is arranged in sheath 1 in, and sheath 1 material is non-magnetic material, and permanent magnet 2's material is tombarthite neodymium iron boron or tombarthite samarium cobalt material, and this permanent magnet is cylindrical or ring shape, and parallel magnetization along cylinder or ring radius direction respectively. Specifically, the sheaths 1 on the outer sides of both ends of the permanent magnet 2 form insertion parts 11 for respectively inserting and fixing the first spindle 41 and the second spindle 42 on both sides; the first mandrel 41 and the second mandrel 42 are both hollow structures, and as shown in the figure, the inserting part 11 serving as an assembly adapting structure is formed by the outer end part of the sheath 1 which extends outwards in the axial direction, so that the weight of the rotor is effectively reduced based on the mandrel with a light weight design, the axial size of the outer end part of the inserting part 11 can be reduced to the maximum extent, and the assembly operation is convenient on the basis of meeting the purpose of the invention of reducing the weight of a product.

It should be noted that, the terms "first" and "second" are used herein to define the same functional components or structures, so as to clearly show the dynamic matching relationship of the whole machine. The expressions "first", "second", etc. do not have a substantial limiting effect on the corresponding functional components or structures.

In addition, the terms of orientation such as "inner" and "outer" used herein are defined with reference to the central permanent magnet 2, that is, axially inward toward the permanent magnet 2 and axially outward away from the permanent magnet 2. It should be understood that the above directional terms are used only for clearly describing the relative positional relationship between the components of the present solution.

Wherein, the bottom wall of the mandrel (41, 42) at the two sides opposite to the permanent magnet 2 is provided with a first through hole 43, and the side wall of the mandrel (41, 42) at the outer side of the sheath 1 is provided with a second through hole 44, thereby forming a corresponding exhaust channel. With such an arrangement, when the mandrels (41, 42) are assembled, the first through hole 43 can construct an air discharge channel in the area between the mandrels (41, 42) and the permanent magnet 2, and the mandrels and the permanent magnet can be completely abutted and assembled without a gap, so that the axial assembly error is reduced.

In the actual working process, the sheath 1 and the permanent magnet 2 generate heat due to the eddy current effect, and the internal gas of the hollow structure of the mandrel (41, 42) is heated and expanded through heat conduction between metals. In the scheme, based on the arrangement of the second through holes 44 on the mandrels (41, 42), the gas expanded by heat in the hollow structure can be effectively removed in real time, so that the mandrels (41, 42) can be prevented from bearing larger gas pressure by self structures, and the safety and reliability of operation are ensured.

In order to obtain better processing manufacturability, the mandrels (41, 42) can be further optimized, and as shown in the figure, the first mandrel 41 and the second mandrel 42 both adopt a split structure, the first mandrel 41 is composed of a first mandrel body 411 and a first adapter 412, and the second mandrel is composed of a second mandrel body 421 and a second adapter 422. Here, the material of the mandrel body (411, 421) is a non-magnetic material.

The mandrel bodies (411, 421) are integrally cylindrical, one end of each mandrel body is provided with an opening, the bottom sides of the mandrel bodies are fixedly inserted into the insertion parts 11 on the corresponding sides, and the mandrel bodies (411, 421) and the insertion parts 11 are fixed in an interference fit mode and/or a welding mode. Correspondingly, the first through hole 43 is arranged at the bottom of the mandrel body (411, 421); please refer to fig. 2, which is a schematic view of the overall structure of the mandrel body. As shown in the drawing, the first through hole 43 is provided at one of the axial center positions. Of course, in theory, the first through holes 43 may be provided in a plurality (not shown) uniformly distributed in the circumferential direction, so that the air between the spindles (41, 42) and the permanent magnet 2 can be exhausted in a more timely manner during assembly.

Wherein, the adapter (412, 422) is connected with the opening of the corresponding mandrel body (411, 421) in a sealing way to form the hollow structure, and correspondingly, the second through hole 44 is opened on the side wall of the adapter (412, 422). Please refer to fig. 3, which is a schematic diagram of the overall structure of the adapter. In this embodiment, the second through holes 44 are preferably provided in a plurality that are evenly distributed in the circumferential direction, such as but not limited to two symmetrically provided second through holes 44 shown in the figure.

Of course, according to the requirement of a specific product, the second through hole 44 may also be opened on the mandrel body (411, 421), or the second through hole 44 may be opened on the side walls of the mandrel body (411, 421) and the adaptor (412, 422), so long as the functional requirements of air exhaust in the cavity and good dynamic balance can be considered, which are all within the scope of the present application.

The impellers are respectively installed on the mandrels on the two sides of the scheme. As shown, the first adapter 412 is provided with a first hub 4121 formed to axially overhang for mounting the first impeller 31; the second adapter 422 is provided with a second hub 4221 formed to axially outwardly extend for mounting the first impeller 32. In order to obtain a good working seal, a first sealing disk 51 is fixedly arranged on the wheel shaft 4121 on the inner side of the first impeller 31, a second sealing disk 52 is fixedly arranged on the wheel shaft 4221 on the inner side of the second impeller 32, and a plurality of sealing rings are preferably formed on the outer peripheral surfaces of the two sealing disks and used for forming a labyrinth sealing pair with a sealing channel (not shown in the figure) on a motor end cover; the sealing pair formed here is not limited to the labyrinth seal constructed, as long as the functional requirements are met.

Wherein, the first wheel axle 4121 is fixedly provided with a thrust disc 6, the thrust disc 6 is located inside the first sealing disc 51, and the thrust disc 6 is a part of a common axial bearing structure and is not described herein again. Meanwhile, the outer end parts of the wheel shafts (4121, 4221) are provided with threaded sections adapted to the nuts to lock the impellers (31, 32) mounted on the respective wheel shafts, specifically, the first nut 71 and the second nut 72 have different locking rotation directions, and in the present two-stage rotor embodiment, when the rotor rotation direction is counterclockwise as viewed from the first wheel shaft 4121 side, the thread direction of the first nut 71 should be a right-handed locking nut, and the thread direction of the second nut 72 should be a left-handed locking nut.

Further, a cylindrical first connection portion 4122 inserted and fitted to the first spindle body 411 is disposed inside the wheel shaft of the first adapter 412, and a cylindrical second connection portion 4222 inserted and fitted to the second spindle body 421 is disposed inside the wheel shaft of the second adapter 422. After the assembly is finished, the cylindrical connecting parts (4122, 4222) are respectively inserted into the mandrel bodies (411, 421), the cylindrical connecting parts (4122, 4222) of the adapter are fixed with the corresponding mandrel bodies (411, 421) in an interference fit and/or welding mode, and the reliability of the assembly relationship between the cylindrical connecting parts and the corresponding mandrel bodies can be further improved through the arrangement of the axial matching length.

It can be understood that the lightweight design of the two-stage rotor structure proposed by the present invention is also applicable to the single-stage rotor structure described in the second embodiment.

Example two:

referring to fig. 4, there is shown an assembly view of the rotor structure according to the present embodiment, in which the single-stage rotor is applicable to a single-stage type impeller air compressor. The core design concept of the scheme is the same as that of the first embodiment, and in order to clearly show the difference and the connection between the two, the same functional components and structures are indicated by the same reference numerals in the figures.

Similarly, the permanent magnet 2 is built in the sheath 1, and the insertion portions 11 are formed in the sheath 1 outside both ends of the permanent magnet 2. Wherein, one side is inserted and fixed with a first mandrel 41 used for installing the first impeller 31, the other side is inserted and fixed with a mandrel 8 without an impeller, the mandrel 8 also adopts a hollow structure consistent with the first mandrel 41, so as to effectively reduce the weight of the rotor.

The mandrel 8 may adopt a split structure to obtain better processing manufacturability, and as shown in fig. 4, the mandrel 8 is composed of a mandrel body 81 and an adapter 82. Specifically, the mandrel body 81 is integrally cylindrical with an opening formed at one end, the bottom side of the mandrel body 81 is inserted and fixed into the insertion portion 11 on the corresponding side, the mandrel body 81 and the insertion portion 11 are fixed by interference fit and/or welding, and accordingly, the first through hole 43 on the side is opened at the bottom of the mandrel body 81 to exhaust gas between the permanent magnet 2 and the mandrel body in the assembling process.

The adapter 82 of the mandrel 8 is a cover, and a spigot structure is arranged on the adapter side of the cover to be inserted and fixed in the opening of the mandrel body 81. The second through hole 44 on the side is opened on the side wall of the mandrel body 81, and internal gas expanded by heat in the hollow structure is exhausted at the same time, so that the safety and the reliability of operation are ensured.

In this embodiment, the locking rotation direction of the first nut 71 is also determined according to the rotation direction of the motor or the air compressor, and in the present single-stage rotor embodiment, when the rotor rotation direction is counterclockwise as viewed from the first wheel shaft 4121 side, the thread direction of the first nut 71 should be a right-handed locking nut. Other components are the same as those in the first embodiment, and are not described herein again.

In addition to the aforementioned rotor structure, the present embodiment provides a motor including a stator and a rotor using the aforementioned rotor structure. Other functional structures of the motor are not the core invention of the present application, and can be realized by those skilled in the art based on the prior art, so that the details are not described herein.

In addition to the above-described rotor structure and motor, the present embodiment provides an air compressor using the above-described motor, and it should be also noted that. Other functional structures of the air compressor are not the core invention points of the present application, and can be realized by a person skilled in the art based on the prior art, so that the details are not described herein.

In particular, the hollow spindle of the rotor structure provided in the present embodiment is not limited to the two-part structure shown in the drawings, and it is to be understood that the hollow spindle may also be in other split forms, and it is within the scope of the present invention as long as the core inventive concept of the present invention is applied.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that it is obvious to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and these modifications and improvements should also be considered as the protection scope of the present invention.

Claims

1. A rotor structure, comprising:

a sheath;

the permanent magnet is arranged in the sheath, and the sheaths on the outer sides of the two ends of the permanent magnet form inserting parts;

the mandrels on the two sides are respectively inserted and fixed in the insertion parts on the two sides of the sheath, and the mandrels are of hollow structures; the bottom wall of the mandrel, which is opposite to the permanent magnet, is provided with a first through hole, and the side wall of the mandrel, which is positioned outside the sheath, is provided with a second through hole.

2. The rotor structure of claim 1, wherein the mandrel comprises:

the mandrel body is integrally cylindrical, an opening is formed in one end of the mandrel body, the bottom side of the mandrel body is inserted and fixed in the insertion part on the corresponding side, and the first through hole is formed in the bottom of the mandrel body;

the adapter body is connected with the opening of the mandrel body in a sealing mode to form the hollow structure, and the second through hole is formed in the side wall of the adapter body and/or the mandrel body.

3. The rotor structure according to claim 2, wherein the first through hole is provided as one at an axial position or as a plurality of circumferentially and uniformly distributed; the second through holes are circumferentially and uniformly distributed.

4. The rotor structure according to claim 3, wherein the rotor structure is a two-stage rotor, and the adapters on both sides of the spindle are provided with an axially outwardly extending hub for mounting an impeller; a sealing disc is fixedly arranged on the wheel shaft on the inner side of the impeller and used for forming a sealing pair with a sealing channel on a motor end cover; and a thrust disc is fixedly arranged on one wheel shaft and is positioned on the inner side of the sealing disc.

5. The rotor structure according to claim 3, wherein the rotor structure is a single-stage rotor, and the adapter body of the spindle on one side is provided with an axially outwardly extending hub for mounting an impeller; a sealing disc is fixedly arranged on the wheel shaft on the inner side of the impeller and used for forming a sealing pair with a sealing channel on a motor end cover, a thrust disc is fixedly arranged on the wheel shaft and is positioned on the inner side of the sealing disc; the adapter body of the mandrel on the other side is a cover body.

6. A rotor structure according to claim 4 or 5, characterised in that the adapter body inside the wheel shaft is provided with a cylindrical connection part which is in plug-in fit with the spindle body, and the outer end of the wheel shaft is provided with a threaded section for fitting with a nut for locking an impeller mounted on the respective wheel shaft.

7. The rotor structure of claim 2, wherein the mandrel body and the insertion portion are fixed by interference fit and/or welding, and the adapter and the mandrel body are fixed by interference fit and/or welding.

8. The rotor structure of claim 7, wherein the material of the sheath and the mandrel body is a non-magnetic conductive material; the permanent magnet is made of rare earth neodymium iron boron or rare earth samarium cobalt, is cylindrical or annular, and is magnetized in parallel along the radius direction of the cylinder or the ring respectively.

9. An electrical machine comprising a rotor and a stator adapted to each other, wherein the rotor is configured as a rotor according to any one of claims 1 to 8.

10. Air compressor comprising an electric motor, characterized in that said electric motor is an electric motor according to claim 9.