CN112953065A

CN112953065A - Connecting structure of rotor and crankshaft and motor with same

Info

Publication number: CN112953065A
Application number: CN202110179462.4A
Authority: CN
Inventors: 萧晓森
Original assignee: Gree Green Refrigeration Technology Center Co Ltd of Zhuhai
Current assignee: Gree Green Refrigeration Technology Center Co Ltd of Zhuhai
Priority date: 2021-02-09
Filing date: 2021-02-09
Publication date: 2021-06-11
Anticipated expiration: 2041-02-09
Also published as: CN112953065B

Abstract

The invention provides a connecting structure of a rotor and a crankshaft and a motor with the connecting structure. The connection structure of the rotor and the crankshaft includes: a crankshaft; the rotor core is provided with a mounting hole, and the crankshaft is inserted into the mounting hole; the rotor core comprises a core block; and the transmission structure is connected with the crankshaft, at least part of the transmission structure is movably arranged along the radial direction of the rotor, and at least part of the transmission structure is connected with the iron core block so as to drive the iron core block to move along the radial direction of the rotor. The connecting structure of the rotor and the crankshaft solves the problem that the air gap between the rotor and the stator cannot be adjusted in the prior art.

Description

Connecting structure of rotor and crankshaft and motor with same

Technical Field

The invention relates to the field of motors, in particular to a connecting structure of a rotor and a crankshaft and a motor with the connecting structure.

Background

The air gap between the stator and rotor of an electric machine is an important parameter for the design of the performance and noise optimization of the electric machine. On one hand, the design of the small air gap is beneficial to improving the output torque of the motor, reducing the power loss and improving the running performance of the motor. At the same time, however, the design of a small air gap, under some operating conditions, may increase the electromagnetic noise of the motor due to its high air gap flux density. Therefore, the air gap between the stator and the rotor is reduced, the harmonic flux density of the air gap can be improved, the power coefficient of the motor is improved, the output torque of the motor is increased, and meanwhile, the electromagnetic noise is increased and needs to be comprehensively considered. The air gap is increased, the electromagnetic noise of the motor can be obviously reduced, but the larger the air gap is, the better the air gap is, because the air gap is too large, the leakage reactance and the transient reactance of the motor can be reduced, the starting current can be increased, and the basic loss can be increased. How to design a proper stator-rotor air gap and simultaneously ensure the high performance and low noise of the motor is a difficult point of motor design.

Nowadays, the permanent magnet synchronous motor applied to the field of variable frequency compressors has higher and higher requirements on performance and noise, and the design difficulty of the permanent magnet synchronous motor and the noise is higher. Because the operating condition of the variable frequency compressor is changed, the performance and the noise performance of the same motor are different when the same motor operates under different operating conditions. Some working conditions have high performance and low noise; some working conditions have high performance and high noise; some working conditions have low performance but low noise; some working conditions have low performance and high noise. To this kind of condition, designer all can carry out certain design of choosing usually, for example to the operating mode of high noise, increases motor stator and rotor air gap, has obvious noise reduction effect, but the performance to the operating mode that other noises are low simultaneously has certain weakening. Or other noise reduction measures such as optimizing a pipeline, wrapping soundproof cotton and the like are additionally arranged on the external structure of the compressor.

However, the air gap between the stator and the rotor of the motor cannot be adjusted according to different working conditions, and the contradiction between performance optimization and noise optimization cannot be solved.

Disclosure of Invention

The invention mainly aims to provide a connecting structure of a rotor and a crankshaft and a motor with the connecting structure, so as to solve the problem that an air gap between the rotor and a stator cannot be adjusted in the prior art.

In order to achieve the above object, according to one aspect of the present invention, there is provided a connection structure of a rotor and a crankshaft, comprising: a crankshaft; the rotor core is provided with a mounting hole, and the crankshaft is inserted into the mounting hole; the rotor core comprises a core block; and the transmission structure is connected with the crankshaft, at least part of the transmission structure is movably arranged along the radial direction of the rotor, and at least part of the transmission structure is connected with the iron core block so as to drive the iron core block to move along the radial direction of the rotor.

Further, the crankshaft has a fluid passage; the transmission structure comprises a piston and a moving part connected with the piston, the piston is arranged in the fluid channel to divide the fluid channel into a first cavity and a second cavity, the first cavity is positioned on one side of the second cavity, which is far away from the moving part, and the first cavity is used for introducing fluid; the moving member is connected with the iron core block.

Further, the moving part is provided with an accommodating cavity; the transmission structure further includes: the stop piece is connected with the piston and arranged in the accommodating cavity; the elastic piece is arranged in the accommodating cavity and is positioned between the stop piece and the bottom wall of the accommodating cavity.

Further, the transmission structure further comprises: one end of the connecting rod is connected with the piston, and the connecting rod is inserted in the second cavity and the accommodating cavity; the stop piece is connected with the connecting rod; the elastic piece is sleeved on the connecting rod.

Furthermore, an adjusting groove and a first communicating hole are arranged on the crankshaft, and the first communicating hole is communicated with the adjusting groove; the moving piece comprises a first mounting part and a connecting part, and the first mounting part is movably arranged in the adjusting groove; one end of the connecting part is connected with the first mounting part, and the other end of the connecting part penetrates through the first communicating hole and then is connected with the iron core block.

Furthermore, the moving piece also comprises a second mounting part which is connected with the connecting part; the iron core block is provided with a mounting groove and a second communicating hole, and the second communicating hole is communicated with the mounting groove; connecting portion wear to establish in the second communicating hole, and second installation department fixed mounting is in the mounting groove.

Further, the moving part is provided with an accommodating cavity; the transmission structure also comprises a stop piece, and the stop piece is connected with the piston and arranged in the accommodating cavity; the stop piece is connected with the moving piece; the crankshaft further comprises a tubular structure, the tubular structure is arranged in the adjusting groove, at least part of the tubular structure is inserted into the accommodating cavity, and one end, far away from the axis of the crankshaft, of the tubular structure is used for stopping the stop piece.

Further, a third communication hole is provided in the core block, the third communication hole extending in the axial direction of the rotor.

Further, the rotor core comprises a plurality of core blocks, and the plurality of core blocks are sequentially arranged around the circumferential direction of the crankshaft; the transmission structures are multiple, the transmission structures and the iron core blocks are arranged in a one-to-one correspondence mode, and each transmission structure is connected with the corresponding iron core block.

According to another aspect of the present invention, there is provided an electric motor including a connection structure of a rotor and a crankshaft, wherein the connection structure of the rotor and the crankshaft is the above-mentioned connection structure of the rotor and the crankshaft.

The connecting structure of the rotor and the crankshaft comprises the crankshaft, a rotor iron core and a transmission structure, wherein the rotor iron core is connected with the crankshaft through the transmission structure, and can do reciprocating linear motion in the radial direction of the rotor under the action of the transmission structure, so that the dynamic adjustment of an air gap between the rotor and the stator is realized, the contradiction between the optimization of the performance of the motor and the optimization of noise is solved, and the performance and the noise of the motor can obtain the optimal effect.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic structural view showing an embodiment of a connection structure of a rotor and a crankshaft according to the present invention;

FIG. 2 is a schematic structural view showing an embodiment of a connecting structure of a rotor and a crankshaft according to the present invention;

fig. 3 is a schematic structural view showing a rotor core of the rotor-crankshaft connecting structure according to the present invention;

fig. 4 shows a schematic representation of the crankshaft and the gear mechanism of the rotor-crankshaft connection according to the invention.

Wherein the figures include the following reference numerals:

10. a crankshaft; 11. a fluid channel; 111. a first cavity; 112. a second cavity; 12. an adjustment groove; 13. a first communication hole; 14. a tubular structure; 20. a rotor core; 21. mounting holes; 22. a core block; 221. mounting grooves; 222. a second communication hole; 223. a third communication hole; 224. buckling points; 225. a permanent magnet; 30. a transmission structure; 31. a piston; 32. a moving member; 321. a first mounting portion; 322. a connecting portion; 323. a second mounting portion; 324. an accommodating cavity; 33. a stopper; 34. an elastic member; 35. a connecting rod.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The present invention provides a connection structure of a rotor and a crankshaft, referring to fig. 1 to 4, including: a crankshaft 10; a rotor core 20, the rotor core 20 having a mounting hole 21, the crankshaft 10 being inserted in the mounting hole 21; the rotor core 20 includes core blocks 22; and a transmission structure 30 connected with the crankshaft 10, at least a part of the transmission structure 30 being movably disposed along a radial direction of the rotor, and at least a part of the transmission structure 30 being connected with the core blocks 22 to move the core blocks 22 along the radial direction of the rotor.

The connecting structure of the rotor and the crankshaft comprises the crankshaft 10, a rotor iron core 20 and a transmission structure 30, wherein the rotor iron core 20 is connected with the crankshaft 10 through the transmission structure 30, and the rotor iron core 20 can do reciprocating linear motion in the radial direction of the rotor under the action of the transmission structure 30, so that the dynamic adjustment of an air gap between the rotor and a stator is realized, the contradiction between the optimization of the performance of the motor and the optimization of noise is solved, and the performance and the noise of the motor can obtain the optimal effect.

Specifically, the connection structure of the rotor and the crankshaft comprises a rotor, the rotor comprises a rotor core 20, and the rotor and the crankshaft are connected through a transmission structure 30.

Specifically, rotor core 20 is assembled to crankshaft 10.

In the present embodiment, the crankshaft 10 has a fluid passage 11; the transmission structure 30 comprises a piston 31 and a moving part 32 connected with the piston 31, the piston 31 is arranged in the fluid passage 11 to divide the fluid passage 11 into a first cavity 111 and a second cavity 112, the first cavity 111 is located on one side of the second cavity 112 far away from the moving part 32, and the first cavity 111 is used for introducing fluid; the moving member 32 is connected to the core block 22. Such an arrangement enables movement of the moving member 32 in the radial direction.

Specifically, the first chamber 111 is connected with a gas supply structure to ventilate the first chamber 111.

In the present embodiment, the moving member 32 has a receiving cavity 324; the transmission structure 30 further includes: a stopper 33 connected with the piston 31 and disposed within the accommodation chamber 324; and an elastic member 34 disposed in the receiving cavity 324 between the stopper 33 and the bottom wall of the receiving cavity 324. Specifically, the stopper 33 is connected to both the elastic member 34 and the moving member 32. When the fluid is introduced into the first cavity 111, the stopper 33 presses the elastic member 34, and further presses the moving member 32 to move, and when the fluid is stopped being introduced into the first cavity 111, the elastic member 34 recovers its shape, so as to drive the moving member 32 to return. Moreover, the elastic piece 34 can play a role in buffering, and collision between parts is avoided.

In particular, the elastic member 34 is a spring.

In this embodiment, the transmission structure 30 further includes: a connecting rod 35, one end of the connecting rod 35 is connected with the piston 31, and the connecting rod 35 is inserted in the second cavity 112 and the accommodating cavity 324; the stop piece 33 is connected with the connecting rod 35; the elastic member 34 is fitted over the connecting rod 35. Such an arrangement serves to limit the elastic member.

In the present embodiment, the crankshaft 10 is provided with an adjustment groove 12 and a first communication hole 13, and the first communication hole 13 is communicated with the adjustment groove 12; the moving member 32 includes a first mounting portion 321 and a connecting portion 322, the first mounting portion 321 being movably disposed in the adjustment groove 12; one end of the connecting portion 322 is connected to the first mounting portion 321, and the other end of the connecting portion 322 passes through the first communication hole 13 and is connected to the core block 22.

In this embodiment, the moving member 32 further includes a second mounting portion 323, and the second mounting portion 323 is connected to the connecting portion 322; the core block 22 is provided with a mounting groove 221 and a second communication hole 222, and the second communication hole 222 is communicated with the mounting groove 221; the connection portion 322 is inserted into the second communication hole 222, and the second mounting portion 323 is fixedly mounted in the mounting groove 221.

Specifically, the first and second mounting

parts

321 and 323 are disposed at opposite sides of the connection part 322.

Specifically, the mounting groove 221 and the second communication hole 222 are T-shaped in cross section in a direction perpendicular to the axial direction of the rotor. That is, the mounting groove 221 and the second communication hole 222 are vertically disposed.

In the present embodiment, the moving member 32 has a receiving cavity 324; the transmission structure 30 further comprises a stopper 33, the stopper 33 being connected with the piston 31 and disposed inside the housing cavity 324; the stopper 33 is connected with the moving member 32; crankshaft 10 further includes a tubular structure 14, tubular structure 14 being disposed in adjustment slot 12, at least part of tubular structure 14 being inserted in receiving cavity 324, an end of tubular structure 14 remote from the axis of crankshaft 10 serving to stop against stop 33. Such an arrangement serves to limit the limit position of the moving member 32, to prevent the moving member 32 from colliding with the crankshaft 10, and also to prevent the core blocks 22 from colliding with the crankshaft 10.

In the present embodiment, the core block 22 is provided with a third communication hole 223, and the third communication hole 223 extends in the axial direction of the rotor; the core blocks 22 have a first end face and a second end face disposed oppositely in the axial direction of the rotor, and the third communication holes 223 extend from the first end face to the second end face. The provision of the third communication hole 223 realizes the assembly of the core block 22 with other parts.

Specifically, the third communication hole 223 is a rivet hole.

In the present embodiment, the rotor core 20 includes a plurality of core blocks 22, the plurality of core blocks 22 being sequentially arranged around the circumferential direction of the crankshaft 10; the number of the transmission structures 30 is multiple, the transmission structures 30 are arranged in one-to-one correspondence with the iron core blocks 22, and each transmission structure 30 is connected with a corresponding iron core block 22. Specifically, the rotor core with the block design divides the rotor core into blocks according to the number of poles, and evenly divides the rotor core with N poles into N core blocks 22 according to the center division mode, and each core block 22 has a complete rotor magnetic pole structure. Taking fig. 1 and 2 as an example, a 4-pole rotor core is divided into 4 core blocks 22 in a centrosymmetric manner.

Specifically, the crankshaft 10 has a plurality of fluid passages 11, the plurality of fluid passages 11 are designed in one-to-one correspondence with the plurality of transmission structures 30, and the piston 31 of each transmission structure 30 is disposed in the corresponding fluid passage 11. Specifically, the first chambers 111 of the respective fluid passages 11 are supplied with air through different air supply structures, respectively.

Specifically, the dynamic change of the radial position of the rotor core is controlled through the rotor core designed in a blocking mode and the transmission structure 30 connected with the rotor core, so that the effective adjustment of the air gap between the stator and the rotor of the motor is realized, the air gap adjustment range can reach 1-3 times of the minimum air gap, the air gap flux density between the stator and the rotor is adjusted, the noise of the motor is optimized, and the performance of the motor is improved.

Specifically, the rotor core designed by blocking can be adjusted according to different working condition requirements, and each core block 22 mainly performs the following two adjustment modes: the same displacement stroke adjustment is carried out on each iron core block 22, so that the air gap is uniformly adjusted; the iron core blocks 22 are adjusted in different displacement strokes, so that the air gap is adjusted non-uniformly. The distribution condition of the air-gap magnetic field can be further adjusted, the air-gap flux density waveform of the stator and the rotor under different working conditions is improved, the harmonic loss and the electromagnetic noise of the motor during operation are reduced, and the performance of the motor is improved.

In specific implementation, as shown in fig. 1, the stroke of the transmission structure 30 is 0, and the motor is in a state when the maximum air gap is reached, as shown in fig. 2, the transmission structure 30 is in a state when the maximum stroke is reached, and the maximum air gap is set to be 1-3 times of the minimum air gap when the motor is in a state when the minimum air gap is reached. Meanwhile, different displacement stroke adjustments can be carried out on different iron core blocks 22, so that the air gaps of the stator and the rotor become uneven, the effect of further fine adjustment is achieved, and the air gap adjustment has more schemes.

In this embodiment, the iron core block 22 is formed by stacking a plurality of iron core block punching sheets, each iron core block punching sheet is provided with a plurality of fastening points 224 arranged at intervals, and two adjacent iron core block punching sheets are connected through the fastening points 224; the buckling point 224 is a protruding structure, a concave part matched with the protruding structure is arranged on the adjacent iron core block punching sheets, and the two adjacent iron core block punching sheets are connected through the protruding structure clamped in the concave part.

In the present embodiment, the connection structure of the rotor and the crankshaft includes a plurality of sets of transmission structures 30, each set of transmission structure 30 includes a plurality of transmission structures 30, and each transmission structure 30 of each set of transmission structure 30 is connected to a corresponding iron core block 22; the sets of transmission structures 30 are arranged at intervals along the axial direction of the rotor. Specifically, a set of transmission structures 30 are provided at intervals of 20-30mm in height according to the height of the rotor core in the axial direction. Such an arrangement achieves smooth control of the core blocks 22 and prevents the core blocks 22 from being inclined.

In the present embodiment, each of the core blocks 22 is provided with a permanent magnet 225.

The invention also provides a motor which comprises a connecting structure of the rotor and the crankshaft, wherein the connecting structure of the rotor and the crankshaft is the connecting structure of the rotor and the crankshaft in the embodiment.

The application provides the connection structure of the rotor and the crankshaft with the dynamic air gap adjusting function, and the connection structure is applied to a radial magnetic field motor, and can adjust the proper air gap between the stator and the rotor in real time according to the noise and performance requirements of different operation conditions, so that the performance and the noise of the motor can both obtain the optimal effect. Meanwhile, due to the modularized design, the rotor core can be subjected to uniform air gap adjustment of the outer diameter all the time and non-uniform air gap adjustment of different outer diameters, and more complex and changeable working conditions can be met by multiple adjustment modes.

The method and the device realize effective adjustment of the air gap of the stator and the rotor of the motor under the closed condition, and solve the problem of contradiction between performance pursuit and noise optimization caused by fixed air gap of the stator and the rotor of the permanent magnet synchronous motor and incapability of real-time adjustment.

The beneficial effect of this application: the rotor core can move radially in a certain range, the position of the rotor core is adjusted in real time, the stator and rotor air gap distance is changed, and the stator and rotor air gap flux density is adjusted. The same motor can reach the corresponding optimal air gap according to different operation conditions. The requirements of high-efficiency operation and noise reduction are balanced and the requirements of various working conditions are met by adjusting the air gaps of the stator and the rotor; the modularized design can enable the air gap adjustment to have multiple adjustment schemes, and the same displacement adjustment of each module can be carried out through the dynamic reciprocating structure of each module to form a uniform air gap, or each module can carry out different displacement adjustment to form an uneven air gap, so that the distribution condition of an air gap magnetic field is adjusted, the magnetic density waveform of a stator air gap and a rotor air gap under different working conditions is improved, the harmonic loss and the electromagnetic noise of the motor during operation are reduced, and the performance of the motor is improved; through the rotor core and the crankshaft of this application, can be in the source, in motor and pump body structure, realize the high performance and fall the design demand of making an uproar, reduce external noise and optimize the structure for the outer machine structure of air conditioner is compacter.

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects:

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A connecting structure of a rotor and a crankshaft, comprising:

a crankshaft (10);

a rotor core (20), the rotor core (20) having a mounting hole (21), the crankshaft (10) being inserted in the mounting hole (21); the rotor core (20) includes core blocks (22);

and the transmission structure (30) is connected with the crankshaft (10), at least part of the transmission structure (30) is movably arranged along the radial direction of the rotor, and at least part of the transmission structure (30) is connected with the iron core block (22) so as to drive the iron core block (22) to move along the radial direction of the rotor.

2. A rotor to crankshaft connection according to claim 1, characterized in that the crankshaft (10) has a fluid passage (11); the transmission structure (30) comprises a piston (31) and a moving part (32) connected with the piston (31), the piston (31) is arranged in the fluid channel (11) to divide the fluid channel (11) into a first cavity (111) and a second cavity (112), the first cavity (111) is positioned on one side of the second cavity (112) far away from the moving part (32), and the first cavity (111) is used for introducing fluid; the moving member (32) is connected with the core block (22).

3. A rotor and crankshaft connection according to claim 2, wherein said moving member (32) has a receiving cavity (324); the transmission structure (30) further comprises:

a stopper (33) connected to the piston (31) and disposed within the housing cavity (324);

an elastic member (34) disposed within the accommodation cavity (324) and between the stopper (33) and a bottom wall of the accommodation cavity (324).

4. A rotor to crankshaft connection according to claim 3, characterized in that said transmission structure (30) further comprises:

a connecting rod (35), one end of the connecting rod (35) being connected with the piston (31), the connecting rod (35) being inserted in the second cavity (112) and the accommodating cavity (324); the stop piece (33) is connected with the connecting rod (35); the elastic piece (34) is sleeved on the connecting rod (35).

5. The structure for connecting a rotor and a crankshaft according to claim 2, characterized in that the crankshaft (10) is provided with an adjustment groove (12) and a first communication hole (13), the first communication hole (13) communicating with the adjustment groove (12); the moving piece (32) comprises a first mounting part (321) and a connecting part (322), and the first mounting part (321) is movably arranged in the adjusting groove (12); one end of the connecting part (322) is connected with the first mounting part (321), and the other end of the connecting part (322) penetrates through the first through hole (13) and then is connected with the iron core block (22).

6. The connecting structure of a rotor and a crankshaft according to claim 5, wherein the moving member (32) further includes a second mounting portion (323), the second mounting portion (323) being connected to the connecting portion (322); the iron core block (22) is provided with a mounting groove (221) and a second communication hole (222), and the second communication hole (222) is communicated with the mounting groove (221); the connecting part (322) is arranged in the second communication hole (222) in a penetrating mode, and the second mounting part (323) is fixedly mounted in the mounting groove (221).

7. A rotor and crankshaft connection according to claim 5, wherein said moving member (32) has a receiving cavity (324); the transmission structure (30) further comprises a stop member (33), the stop member (33) is connected with the piston (31) and is arranged in the accommodating cavity (324); the stop (33) is connected with the moving member (32);

the crankshaft (10) further comprises a tubular structure (14), the tubular structure (14) is arranged in the adjusting groove (12), at least part of the tubular structure (14) is inserted in the accommodating cavity (324), and one end, away from the axis of the crankshaft (10), of the tubular structure (14) is used for stopping the stop piece (33).

8. The structure for connecting a rotor and a crankshaft according to any one of claims 1 to 7, wherein a third communication hole (223) is provided in the core block (22), the third communication hole (223) extending in the axial direction of the rotor.

9. A rotor to crankshaft connection according to any one of claims 1 to 7, wherein the rotor core (20) includes a plurality of core blocks (22), the plurality of core blocks (22) being arranged in sequence around the circumference of the crankshaft (10);

the number of the transmission structures (30) is multiple, the transmission structures (30) and the iron core blocks (22) are arranged in a one-to-one correspondence mode, and each transmission structure (30) is connected with the corresponding iron core block (22).

10. An electric motor comprising a connection structure of a rotor and a crankshaft, characterized in that the connection structure of the rotor and the crankshaft is the connection structure of the rotor and the crankshaft of any one of claims 1 to 9.