CN117439302B - Rotor assembly, motor and magnetic suspension blower - Google Patents

Abstract

The invention provides a rotor assembly, a motor and a magnetic suspension blower, which comprise an optical axis and a magnetic steel group sleeved on the optical axis; the optical axis is formed with the centre bore that runs through self both ends terminal surface, the outer disc of optical axis is provided with along the first recess of axial extension, be provided with the fluid flow path on the optical axis, first recess with the centre bore warp the fluid flow path intercommunication, be provided with first heat-conducting piece in the first recess, first heat-conducting piece with magnet steel group contact, the fluid flow path includes first annular and first through-hole, first annular sets up the optical axis outer disc and along the circumference extension of optical axis, first through-hole radially runs through the optical axis, first through-hole intercommunication the centre bore with first annular to the magnet steel heat dissipation in the motor is unbalanced among the solution prior art, the technical problem that anti demagnetizing ability is weak.

Description

Rotor assembly, motor and magnetic suspension blower

Technical Field

The invention belongs to the technical field of motors, and particularly relates to a rotor assembly, a motor and a magnetic suspension blower.

Background

The cooling problem is always a key and difficult problem in the design and development process of the high-speed motor, and particularly the cooling of the rotor. In the high-speed rotation process of the motor, a large amount of eddy current loss can be generated on the surface of the rotor, particularly the surface-mounted rotor, so that the temperature rise of the motor is too high, once the motor is not cooled well, irreversible demagnetization can be possibly generated, the performance of the motor is seriously influenced, and therefore, how to ensure that the magnetic steel is cooled well is a current problem. In the prior art, the rotor is cooled usually by means of an air gap between the stator and the rotor, radial ventilation cooling is realized by rotating air supply with impellers or forming holes in the stator and the shell, part of heat is taken away by the air channel flowing through the surface of the rotor, obviously, cooling is insufficient, internal magnetic steel cannot be effectively cooled, and the problem of temperature rise of the motor rotor cannot be solved.

Patent KR101407948B1 discloses one kind and gets into inside the motor through in the casing outside air supply, and the wind channel flows through stator and rotor air gap to take away partial heat, this scheme can realize the cooling to the rotor to a certain extent, but the effect is very limited, and compressed air gets into the interior relatively dispersion of casing, and is smaller to the true effective cooling area of rotor, and the cooling effect is not good, does not consider the cooling of magnet steel yet, can't solve motor rotor temperature rise problem.

How to improve the cooling effect of the rotor, especially improve the heat dissipation uniformity and the heat dissipation efficiency of the magnetic steel on the rotor, and then improve the anti-demagnetizing capability of the magnetic steel, is a problem to be solved in the present day.

Disclosure of Invention

Therefore, the invention provides a rotor assembly, a motor and a magnetic suspension blower, which can solve the technical problems of uneven heat dissipation, low heat dissipation efficiency and weak anti-demagnetizing capability of magnetic steel in the motor in the prior art.

In a first aspect, the invention provides a rotor assembly for a motor, comprising an optical axis and a magnetic steel set sleeved on the optical axis;

the optical axis is provided with a central hole penetrating through end surfaces at two ends of the optical axis, the outer circular surface of the optical axis is provided with a first groove extending along the axial direction, the optical axis is provided with a fluid flow path, the first groove is communicated with the central hole through the fluid flow path, a first heat conducting piece is arranged in the first groove, and the first heat conducting piece is in contact with the magnetic steel group;

the fluid flow path comprises a first annular groove and a first through hole, wherein the first annular groove is arranged on the outer circumferential surface of the optical axis and extends along the circumferential direction of the optical axis, the first through hole radially penetrates through the optical axis, and the first through hole is communicated with the central hole and the first annular groove.

In some embodiments, the first heat conducting member is strip-shaped and extends to both ends of the optical axis along the length direction of the first groove;

the first heat conducting piece is provided with a third through hole and a fourth through hole, the third through hole extends along the length of the first heat conducting piece and penetrates through the first heat conducting piece, the inlet of the fourth through hole is led to the first annular groove, and the outlet of the fourth through hole is led to the third through hole.

In some embodiments, a fifth through hole and a second groove are further formed in the first heat conducting member, one surface of the first heat conducting member, which contacts the magnetic steel set, is a convex arc surface, the second groove is located on the convex arc surface and extends to end surfaces of two ends of the first heat conducting member along the length direction of the first heat conducting member, and the fifth through hole is communicated with the second groove and the first annular groove.

In some embodiments, the magnetic steel group is composed of a plurality of magnetic steel units, and a first fluid channel is arranged between two adjacent magnetic steel units and is communicated with the fluid flow path;

a sheath is sleeved outside the magnetic steel group, and the inner circular surface of the sheath is attached to the outer circular surface of the magnetic steel group; the inner circular surface of the sheath is provided with a second annular groove and a third groove, the second annular groove extends along the circumferential direction of the sheath, the third groove extends along the axial direction of the magnetic steel group, and the second annular groove is communicated with the first fluid channel.

In some embodiments, a second heat conducting member is disposed in the third groove, the second heat conducting member includes a concave arc surface contacting with the magnetic steel set, a fourth groove extending along the axial direction of the magnetic steel set is disposed on the concave arc surface, and a second fluid channel communicating the fourth groove with the second ring groove is further disposed on the second heat conducting member.

In some embodiments, a sixth through hole penetrating through the inner circular surface and the outer circular surface of the sheath is formed in the sheath, an opening of the first fluid channel close to the magnetic steel group is an inlet, and an opening of the other end of the first fluid channel is an outlet;

the inlet of the first fluid channel is opposite to the first through hole, and the outlet of the first fluid channel is opposite to the sixth through hole;

or, the inlet of the first fluid channel is offset from the first through hole, and the outlet of the first fluid channel is offset from the sixth through hole.

In some embodiments, a second through hole is disposed on the optical axis, and the second through hole extends to two ends of the optical axis along the axial direction of the optical axis and intersects with the first through hole;

the optical axis is provided with a baffle at least at one end, the baffle comprises a matching surface facing the optical axis, the matching surface is provided with a third annular groove and a fifth groove, the third annular groove extends along the circumferential direction of the optical axis, and the fifth groove extends along the radial direction of the optical axis and is communicated with the third annular groove in a crossing way; the fifth groove extends to the outer peripheral surface of the baffle plate, and the second through hole is communicated with the third annular groove; the third ring groove is adjacent to the optical axis, and the fifth groove is adjacent to the magnetic steel group.

In some embodiments, a fourth ring groove is further arranged on the baffle, the fourth ring groove is sleeved outside the third ring groove, and the fourth ring groove is adjacent to the magnetic steel group.

In a second aspect, the invention also provides an electric machine comprising the rotor assembly.

In a third aspect, the invention provides a magnetic levitation blower comprising the motor.

According to the invention, the first groove is formed in the outer circular surface of the optical axis, the first heat conduction piece is arranged in the first groove, the heat dissipation of the magnetic steel group is accelerated through the first heat conduction piece, the uniformity of the heat dissipation of the magnetic steel is improved, the first annular groove is further formed in the outer circular surface of the optical axis, the contact area of air flow and the first heat conduction piece is further improved, the heat exchange area of the magnetic steel group and air is improved, the heat dissipation of the magnetic steel group is accelerated, and the anti-demagnetizing capability of the magnetic steel group is further improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. The drawings in the following description are merely exemplary and other implementations drawings may be derived from the drawings provided without inventive effort for a person skilled in the art.

FIG. 1 is an exploded view of a first perspective of a rotor assembly according to an embodiment of the present invention;

FIG. 2 is an exploded view of a second perspective of a rotor assembly according to an embodiment of the present invention;

FIG. 3 is an axial schematic view of a rotor assembly according to an embodiment of the present invention in which a first fluid passage is in direct communication with a first through hole and a sixth through hole;

FIG. 4 is an axial schematic view of a rotor assembly according to an embodiment of the present invention with a first fluid passage in offset communication with a first through bore and a sixth through bore;

FIG. 5 is an enlarged view of the portion A in FIG. 4 according to an embodiment of the present invention;

FIG. 6 is an axial cross-sectional view of a second heat transfer member according to an embodiment of the present invention;

FIG. 7 is an axial cross-sectional view of a first heat transfer member according to an embodiment of the present invention;

fig. 8 is a schematic view of the first heat conducting member according to the embodiment of the present invention when the first heat conducting member is provided with the second through hole;

FIG. 9 is a schematic view of a magnetic steel unit according to an embodiment of the present invention disposed in silicon steel;

the reference numerals are expressed as:

1. an optical axis; 101. a central bore; 2. a magnetic steel group; 301. a first groove; 302. a second groove; 303. a third groove; 304. a fourth groove; 305. a fifth groove; 401. a first ring groove; 402. a second ring groove; 403. a third ring groove; 404. a fourth ring groove; 501. a first through hole; 502. a second through hole; 503. a third through hole; 504. a fourth through hole; 505. a fifth through hole; 506. a sixth through hole; 601. a first heat conductive member; 602. a second heat conductive member; 701. a convex arc surface; 702. a concave arc surface; 703. a magnetic steel unit; 704. a sheath; 705. a baffle; 801. a first fluid passage; 802. a second fluid passage.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

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 in accordance with the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.

It should be understood that the term "and/or" as used herein is merely one relationship describing the association of the associated objects, meaning that there may be three relationships, e.g., a and/or B, may represent: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise. It should be understood, however, that the construction, proportion, and size of the drawings, in which the present invention is practiced, are all intended to be illustrative only, and not to limit the scope of the present invention, which should be defined by the appended claims. Any structural modification, proportional change or size adjustment should still fall within the scope of the disclosure without affecting the efficacy and achievement of the present invention. Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

In the description of the present invention, it should be understood that the azimuth or positional relationships indicated by the azimuth terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal", and "top, bottom", etc., are generally based on the azimuth or positional relationships shown in the drawings, merely to facilitate description of the present invention and simplify the description, and these azimuth terms do not indicate and imply that the apparatus or elements referred to must have a specific azimuth or be constructed and operated in a specific azimuth, and thus should not be construed as limiting the scope of protection of the present invention; the orientation word "inner and outer" refers to inner and outer relative to the contour of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "upper surface at … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial location relative 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 in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "over" other devices or structures would then be oriented "below" or "beneath" the other devices or structures. Thus, the exemplary term "above … …" may include both orientations of "above … …" and "below … …". The device may also be positioned in other different ways (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

In addition, the terms "first", "second", etc. are used to define the components, and are only for convenience of distinguishing the corresponding components, and the terms have no special meaning unless otherwise stated, and therefore should not be construed as limiting the scope of the present invention.

The invention belongs to the technical field of motors, and particularly relates to a rotor assembly, a motor and a magnetic suspension blower, which are used for solving the technical problems of unbalanced heat dissipation and weak anti-demagnetization capability of magnetic steel in the motor in the prior art.

Referring to fig. 1-9 in combination, a rotor assembly for a motor includes an optical axis 1 and a magnetic steel set 2 sleeved on the optical axis 1;

the optical axis 1 is provided with a central hole 101 penetrating through end surfaces at two ends of the optical axis 1, an outer circular surface of the optical axis 1 is provided with a first groove 301 extending along an axial direction, a fluid flow path is arranged on the optical axis 1, the first groove 301 is communicated with the central hole 101 through the fluid flow path, a first heat conducting piece 601 is arranged in the first groove 301, and the first heat conducting piece 601 is contacted with the magnetic steel group 2;

the fluid flow path includes a first annular groove 401 and a first through hole 501, the first annular groove 401 is disposed on an outer circumferential surface of the optical axis 1 and extends along a circumferential direction of the optical axis 1, the first through hole 501 radially penetrates the optical axis 1, and the first through hole 501 communicates the central hole 101 with the first annular groove 401.

The cooling medium may be gas or liquid, and when the cooling medium is liquid, it is necessary to specially design the cooling medium to prevent corrosion, short circuit, and the like, and gas cooling is preferably used.

After the gas enters the central hole 101, part of the gas enters the first groove 301 through the fluid flow path and contacts with the first heat conducting member 601; the first heat conducting member 601 contacts with the magnetic steel set 2 and absorbs heat from the magnetic steel set 2, and as the first groove 301 extends along the axial direction of the optical axis 1, the contact area between the first heat conducting member 601 and the magnetic steel set 2 is increased, and the heat can be absorbed from the magnetic steel set 2 in a larger range, so that on one hand, the heat dissipation of the magnetic steel set 2 is quickened, and on the other hand, the degree of the overall temperature unevenness of the magnetic steel set 2 is reduced (the range of the heat absorption from the magnetic steel set 2 is enlarged). The gas contacts with the first heat conduction piece 601 to exchange heat with the first heat conduction piece 601, so that the first heat conduction piece 601 is radiated and cooled, the temperature of the magnetic steel group 2 is finally ensured to be in a proper range, and the anti-demagnetizing capability of the magnetic steel group 2 is improved.

Through the setting, the inside abundant cooling (cooling, heat dissipation) of rotor subassembly is realized, need not to reprocess magnet steel group 2 to reduce the inside temperature when rotor high-speed operation when not influencing the output performance of motor, can effectively solve the inside temperature rise problem of rotor, thereby promote the anti demagnetizing ability of rotor.

The gas enters the first annular groove 401 through the first through hole 501, and exchanges heat with the magnetic steel group 2 when flowing in the first annular groove 401, so that the heat exchange area between the magnetic steel group 2 and the outside is increased, the heat dissipation of the magnetic steel group 2 is further accelerated, and the degree of the overall temperature unevenness of the magnetic steel group 2 is reduced.

The first grooves 301 may be provided in plurality and uniformly arranged on the outer circumferential surface of the optical axis 1 along the circumferential direction of the optical axis 1, the first annular grooves 401 are provided in plurality and distributed along the axial direction of the optical axis 1, the distances between two adjacent first annular grooves 401 are also equal, the first through holes 501 are provided in plurality, and the outlet of each first through hole 501 leading to the first annular groove 401 is located between two adjacent first grooves 301. Therefore, the heat exchange area of the magnetic steel group 2 and the gas is further increased, the contact area of the gas and the first heat conduction piece 601 is increased, the heat dissipation of the magnetic steel group 2 is accelerated, and the anti-demagnetizing capability of the magnetic steel group 2 is improved.

As shown in fig. 2, the axial distance between two adjacent first annular grooves 401 is L,10mm < L < 50mm; as shown in FIG. 4, in the axial direction of the optical axis 1, the included angle formed by two adjacent first grooves 301 and the center of the optical axis 1 is alpha, and the outer machine of the optical axis 1 is D, then D is less than or equal to 100mm,20 degrees < alpha < 60 degrees, 100mm < D is less than or equal to 200mm,15 degrees < alpha < 50 degrees, 200mm < D,10 degrees < alpha < 45 degrees.

Preferably, as shown in fig. 1, 2 and 8, the first heat conducting member 601 is strip-shaped and extends to both ends of the optical axis 1 along the length direction of the first groove 301;

the first heat conducting member 601 is provided with a third through hole 503 and a fourth through hole 504, the third through hole 503 extends along the length of the first heat conducting member 601 and penetrates through the first heat conducting member 601, an inlet of the fourth through hole 504 opens into the first ring groove 401, and an outlet of the fourth through hole 504 opens into the third through hole 503.

The first heat conduction piece 601 is arranged in the first groove 301 and extends to the two ends of the optical axis 1, so that the contact area between the first heat conduction piece 601 and the magnetic steel group 2 is increased;

the gas entering the first ring groove 401 enters the third through hole 503 through the fourth through hole 504 and flows out from both ends of the third through hole 503; the contact area between the gas and the first heat conducting piece 601 is further increased due to the arrangement of the third through holes 503, so that the temperature of the first heat conducting piece 601 is reduced, the temperature difference between the first heat conducting piece 601 and the magnetic steel group 2 is further increased, and the heat dissipation efficiency of the magnetic steel group 2 is improved. The gas is discharged from both ends of the third through hole 503, so that the flow speed of the gas is increased, and the heat dissipation of the gas to the first heat conductive member 601 is further increased.

Preferably, as shown in fig. 7, the first heat conducting member 601 is further provided with a fifth through hole 505 and a second groove 302, a surface of the first heat conducting member 601 contacting the magnetic steel set 2 is a convex arc surface 701, the second groove 302 is located on the convex arc surface 701 and extends to end surfaces of two ends of the first heat conducting member 601 along a length direction of the first heat conducting member 601, and the fifth through hole 505 is communicated with the second groove 302 and the first ring groove 401.

The convex arc surface 701 is completely attached to the magnetic steel set 2, part of the gas entering the third through hole 503 enters the second groove 302 through the fifth through hole 505 and is discharged from the two ends of the second groove 302; because the second groove 302 is located on the convex arc surface 701 contacting with the magnetic steel set 2, when the gas flows in the second groove 302, the gas can not only radiate the first heat conducting piece 601, but also directly exchange heat with the magnetic steel set 2 to radiate the magnetic steel set 2, so that the radiating efficiency of the magnetic steel set 2 is further improved. Here, it is necessary to explain: the contact of the first heat conduction piece 601 with the magnetic steel group 2 can accelerate the heat generated by the magnetic steel group 2 to be transferred to the outside of the magnetic steel group 2, and meanwhile, the speed of the magnetic steel group 2 transferring the heat to the first heat conduction piece 601 is influenced by the contact area between the first heat conduction piece 601 and the magnetic steel group 2 and the temperature difference; the larger the temperature difference between the first heat conductive member 601 and the magnetic steel group 2 is, the larger the contact area is, and the higher the efficiency of transferring heat from the magnetic steel group 2 to the first heat conductive member 601 is. The arrangement of the second groove 302 reduces the contact area between the first heat conducting piece 601 and the magnetic steel group 2, but accelerates the heat dissipation efficiency of the first heat conducting piece 601, is beneficial to expanding the temperature difference between the first heat conducting piece 601 and the magnetic steel group 2, and the gas flowing in the second groove 302 can directly absorb heat from the magnetic steel group 2, so that the arrangement of the second groove 302 can accelerate the heat dissipation efficiency of the magnetic steel group 2 and improve the anti-demagnetizing capability of the magnetic steel group 2.

Preferably, as shown in fig. 3-5, the magnetic steel group 2 is composed of a plurality of magnetic steel units 703, a first fluid channel 801 is disposed between two adjacent magnetic steel units 703, and the first fluid channel 801 is communicated with the fluid flow path;

a sheath 704 is sleeved outside the magnetic steel group 2, and the inner circular surface of the sheath 704 is attached to the outer circular surface of the magnetic steel group 2; the inner circular surface of the sheath 704 is provided with a second ring groove 402 and a third groove 303, the second ring groove 402 extends along the circumferential direction of the sheath 704, the third groove 303 extends along the axial direction of the magnetic steel set 2, and the second ring groove 402 is communicated with the first fluid channel 801.

Combined embodiment one of the magnetic steel unit 703: the magnetic steel units are fan-shaped, and the plurality of magnetic steel units 703 form a ring shape.

When the gas flows in the center hole 101, part of the gas enters the first fluid channel 801 through the fluid flow path, the gas entering the first fluid channel 801 enters the second annular groove 402, and then enters the third groove 303 from the second annular groove 402, and as the second annular groove 402 exchanges heat with the magnetic steel group 2 and the third groove 303 extends along the axial direction of the magnetic steel group 2, the gas absorbs heat to the outer circular surface of the magnetic steel group 2 when flowing in the second annular groove 402 and the third groove 303, so that the heat dissipation of the magnetic steel group 2 is more uniform and rapid. The third groove 303 extends to the end surfaces of the two ends of the sheath 704 along the axial direction of the magnetic steel set 2, and the gas flows out from the end surfaces of the two ends of the sheath 704, so that the flowing speed of the gas in the second annular groove 402 and the third groove 303 is accelerated, and the heat dissipation of the magnetic steel set 2 is improved. Because the first fluid channel 801 is disposed between two adjacent magnetic steel units 703, on one hand, damage to the magnetic steel units 703 is avoided, and on the other hand, heat dissipation is performed on the magnetic steel units 703 when gas flows in the first fluid channel 801, so that the heat dissipation effect of the magnetic steel group 2 is further improved.

As shown in fig. 9, the magnetic steel unit 703 combines the second embodiment: the magnetic steel unit 703 is disposed in the silicon steel, and the silicon steel is sleeved on the optical axis 1, so as to radiate heat from the silicon steel.

Preferably, as shown in fig. 5-6, a second heat conducting member 602 is disposed in the third groove 303, the second heat conducting member 602 includes a concave arc surface 702 contacting the magnetic steel set 2, a fourth groove 304 extending along the axial direction of the magnetic steel set 2 is disposed on the concave arc surface 702, and a second fluid channel 802 that communicates the fourth groove 304 with the second ring groove 402 is further disposed on the second heat conducting member 602.

The second heat conducting piece 602 is arranged in the third groove 303, and the second heat conducting piece 602 accelerates the heat transfer of the magnetic steel group 2 to the outside, so that the heat dissipation efficiency of the magnetic steel group 2 is improved. The concave arc surface 702 of the second heat conducting piece 602 is provided with a fourth groove 304 and a second fluid channel 802 which communicates the fourth groove 304 with the second ring groove 402, when gas flows in the second ring groove 402, the gas enters the fourth groove 304 from the second fluid channel 802, so that heat dissipation of the magnetic steel group 2 is accelerated; the reason why the gas in the fourth groove 304 and the gas flowing in the fourth groove 304 can accelerate the heat dissipation of the magnetic induction ring is basically the same as the reason why the first heat conducting member 601 is arranged, and the heat dissipation reason of the gas to the magnetic steel group 2 when flowing in the second groove 302, except that the second ring groove 402 is positioned at the radial outer side of the first ring groove 401, the gas in the second ring groove 402 is subjected to larger centrifugal force when the rotor assembly rotates, the gas flows in the second ring groove 402 at a higher speed, and the pressure/suction generated by the gas flowing in the second ring groove 402 enables the gas to flow in the fourth groove 304 at a higher speed, so that the heat dissipation efficiency of the magnetic steel group 2 is improved by the faster flow of the gas.

Preferably, the sheath 704 is provided with a sixth through hole 506 penetrating through the inner circular surface and the outer circular surface of the sheath 704, the opening of the first fluid channel 801 near the magnetic steel set 2 is an inlet, and the opening at the other end is an outlet;

as shown in fig. 3, the inlet of the first fluid channel 801 is opposite to the first through hole 501, and the outlet of the first fluid channel 801 is opposite to the sixth through hole 506;

alternatively, as shown in fig. 4 and 5, the inlet of the first fluid channel 801 is offset from the first through hole 501, and the outlet of the first fluid channel 801 is offset from the sixth through hole 506.

An inlet of the first fluid channel 801 is opposite to the first through hole 501, and an outlet of the first fluid channel 801 is opposite to the sixth through hole 506; after the gas is discharged from the first through hole 501 through the first fluid channel 801 and the sixth through hole 506, negative pressure is generated when the gas passes through the second annular groove 402, suction force is generated on the gas in the second annular groove 402, and the gas in the second annular groove 402 is discharged through the first fluid channel 801 and the sixth through hole 506; meanwhile, when the second ring groove 402 flows, the gas in the fourth groove 304 flows into the second ring groove 402 through the second fluid channel 802, and the gas flows in the fourth groove 304 so that the gas enters the fourth groove 304 from the openings at the two ends of the fourth groove 304; similarly, part of the gas enters the second groove 302 from two ends of the second groove 302, and the temperature of the gas entering the second groove 302 is basically the same as that of the gas entering the fourth groove 304, so that the uniformity of heat dissipation of the magnetic steel group 2 is improved (the gas entering the fourth groove 304 directly dissipates heat to the outer circular surface of the magnetic steel group 2, and the gas entering the second groove 302 directly dissipates heat to the inner circular surface of the magnetic steel group 2); in addition, when the gas in the central hole 101 passes through the first fluid channel 801, the gas can radiate the magnetic steel group 2 (radiate the side surfaces of two adjacent magnetic steel units 703), so that the uniformity and efficiency of radiating the magnetic induction group 2 are further improved.

The inlet of the first fluid channel 801 is offset from the first through hole 501 and the outlet of the first fluid channel 801 is offset from the sixth through hole 506; the first fluid passage 801 communicates with the first through hole 501 via the first annular groove 401, and the first fluid passage 801 communicates with the sixth through hole 506 via the second annular groove. In this way, the speed of the gas entering the central hole 101 entering the first through hole 501 is slower, suction force is not generated on the gas in the first annular groove 401 and the second annular groove 402, and the pressure of the gas in the first through hole 501, the first annular groove 401, the first fluid channel 801 and the second annular groove 402 is larger due to the resistance of the gas flowing, and the gas with larger pressure enters the second groove 302 from the first annular groove 401 and the fourth groove 304 from the second annular groove 402; the gas needs to pass through the first annular groove 401 and the first fluid channel 801 before entering the second annular groove 402 (refer to fig. 5), which makes the pressure of the gas in the first annular groove 401 greater than the pressure of the gas in the second annular groove 402, and the reason for the pressure makes the flow speed of the gas in the first annular groove 401 greater than the flow speed of the gas in the second annular groove 402; because the first annular groove 401 is located at the radial inner side of the second annular groove 402, the centrifugal force of the gas in the second annular groove 402 is larger, and the flowing speed of the gas in the second annular groove 402 is higher than that of the gas in the first annular groove 401 due to the centrifugal force; the pressure and the centrifugal force are combined to ensure that the flow speed of the gas in the first annular groove 401 and the second annular groove 402 is balanced, so that the flow speed of the gas when the gas enters the second groove 302 and the fourth groove 304 is balanced, the heat dissipation uniformity of the magnetic steel group 2 is improved, and the phenomenon that the magnetic steel performance is reduced due to the fact that the temperature difference of different parts of the magnetic steel group 2 is large is avoided.

Preferably, as shown in fig. 1 to 4, a second through hole 502 is provided on the optical axis 1, and the second through hole 502 extends to two ends of the optical axis 1 along the axial direction of the optical axis 1 and intersects with the first through hole 501;

at least one end of the optical axis 1 is provided with a baffle 705, the baffle 705 comprises a matching surface facing the optical axis 1, a third ring groove 403 and a fifth groove 305 are arranged on the matching surface, the third ring groove 403 extends along the circumferential direction of the optical axis 1, and the fifth groove 305 extends along the radial direction of the optical axis 1 and is communicated with the third ring groove 403 in a crossing way; the fifth groove 305 extends to the outer peripheral surface of the baffle 705, and the second through hole 502 communicates with the third ring groove 403; the third ring groove 403 is adjacent to the optical axis 1, and the fifth groove 305 is adjacent to the magnetic steel group 2.

The baffle 705 is preferably disk-shaped. Part of gas enters the second through hole 502 from the first through hole 501, the gas flows out of the second through hole 502 and enters the third annular groove 403, the gas flows in the third annular groove 403 to radiate the optical axis 1, the gas flows in the fifth groove 305 to radiate the end face of the magnetic steel group 2, and the optical axis 1 contacts with the magnetic steel group 2, so that the optical axis 1 is cooled to facilitate the radiation of the magnetic steel group 2; in this way, the uniformity and rapidity of heat dissipation to the magnetic steel group 2 are further improved. The gas flows out from one end of the fifth groove 305 (one end extending to the outer peripheral surface of the baffle 705), so that the gas can flow to the radial outer side of the baffle 705 under the action of centrifugal force, thereby accelerating the flow speed of the gas in the third ring groove 403 and the fifth groove 305, and being beneficial to improving the heat dissipation efficiency of the magnetic steel group 2 and the optical axis 1.

Preferably, as shown in fig. 1, a fourth ring groove 404 is further provided on the baffle 705, the fourth ring groove 404 is sleeved outside the third ring groove 403, and the fourth ring groove 404 is adjacent to the magnetic steel group 2.

Since the fifth groove 305 extends to the outer peripheral surface of the baffle 705, the fourth annular groove 404 must intersect with the fourth annular groove 404, and when the gas flows radially outward of the baffle 705 along the fifth groove 305, part of the gas enters the fourth annular groove 404, and since the fourth annular groove 404 is adjacent to the magnetic steel group 2, the gas flows in the fourth groove 304 and can exchange heat with the magnetic steel group 2 to accelerate heat dissipation of the magnetic steel group 2, so that the heat dissipation uniformity of the magnetic induction group 2 is improved, and the overall temperature of the magnetic steel group 2 is more balanced.

The motor provided by the invention comprises the rotor assembly, and is low in temperature rise, good in heat dissipation effect and strong in anti-demagnetizing capability.

A magnetic suspension blower comprises the motor. When the temperature of the air blown out by the magnetic suspension blower is low, a small part of air flow can be led from the air outlet of the magnetic suspension blower to enter the central hole, so that the flow speed of the air is accelerated, and the heat dissipation effect of the magnetic steel group is further accelerated.

Those skilled in the art will readily appreciate that the advantageous features of the various aspects described above may be freely combined and stacked without conflict.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention. The foregoing is merely a preferred embodiment of the present invention, and it should be noted that it will be apparent to those skilled in the art that modifications and variations can be made without departing from the technical principles of the present invention, and these modifications and variations should also be regarded as the scope of the invention.

Claims (9)

1. The rotor assembly is used for a motor and is characterized by comprising an optical axis (1) and a magnetic steel group (2) sleeved on the optical axis (1);

the optical axis (1) is provided with a central hole (101) penetrating through end surfaces at two ends of the optical axis (1), the outer circular surface of the optical axis (1) is provided with a first groove (301) extending along the axial direction, the optical axis (1) is provided with a fluid flow path, the first groove (301) is communicated with the central hole (101) through the fluid flow path, a first heat conducting piece (601) is arranged in the first groove (301), and the first heat conducting piece (601) is in contact with the magnetic steel group (2);

the fluid flow path comprises a first annular groove (401) and a first through hole (501), the first annular groove (401) is arranged on the outer circular surface of the optical axis (1) and extends along the circumferential direction of the optical axis (1), the first through hole (501) radially penetrates through the optical axis (1), and the first through hole (501) is communicated with the central hole (101) and the first annular groove (401);

the magnetic steel group (2) is composed of a plurality of magnetic steel units (703), a first fluid channel (801) is arranged between two adjacent magnetic steel units (703), and the first fluid channel (801) is communicated with the fluid flow path;

a sheath (704) is sleeved outside the magnetic steel group (2), and the inner circular surface of the sheath (704) is attached to the outer circular surface of the magnetic steel group (2); the inner circular surface of the sheath (704) is provided with a second annular groove (402) and a third groove (303), the second annular groove (402) extends along the circumferential direction of the sheath (704), the third groove (303) extends along the axial direction of the magnetic steel group (2), and the second annular groove (402) is communicated with the first fluid channel (801).

2. The rotor assembly according to claim 1, wherein the first heat conducting member (601) is strip-shaped and extends to both ends of the optical axis (1) along a length direction of the first groove (301);

the first heat conduction piece (601) is provided with a third through hole (503) and a fourth through hole (504), the third through hole (503) extends along the length of the first heat conduction piece (601) and penetrates through the first heat conduction piece (601), an inlet of the fourth through hole (504) is led to the first annular groove (401), and an outlet of the fourth through hole (504) is led to the third through hole (503).

3. The rotor assembly according to claim 1, wherein a fifth through hole (505) and a second groove (302) are further formed in the first heat conducting member (601), a face, which is in contact with the magnetic steel group (2), of the first heat conducting member (601 is a convex arc face (701), and the second groove (302) is located on the convex arc face (701) and extends to two end faces of the first heat conducting member (601) along a length direction of the first heat conducting member (601), and the fifth through hole (505) is communicated with the second groove (302) and the first annular groove (401).

4. The rotor assembly according to claim 1, wherein a second heat conducting member (602) is disposed in the third groove (303), the second heat conducting member (602) includes a concave arc surface (702) contacting the magnetic steel set (2), a fourth groove (304) extending along the axial direction of the magnetic steel set (2) is disposed on the concave arc surface (702), and a second fluid channel (802) communicating the fourth groove (304) with the second ring groove (402) is further disposed on the second heat conducting member (602).

5. The rotor assembly according to claim 4, wherein a sixth through hole (506) penetrating through the inner circular surface and the outer circular surface of the sheath (704) is arranged on the sheath (704), an opening of the first fluid channel (801) close to the magnetic steel group (2) is an inlet, and an opening at the other end is an outlet;

-an inlet of the first fluid channel (801) is opposite to the first through hole (501), and an outlet of the first fluid channel (801) is opposite to the sixth through hole (506);

or, the inlet of the first fluid channel (801) is offset from the first through hole (501), and the outlet of the first fluid channel (801) is offset from the sixth through hole (506).

6. The rotor assembly according to any one of claims 1-5, characterized in that a second through hole (502) is provided on the optical axis (1), the second through hole (502) extending along the axial direction of the optical axis (1) to both ends of the optical axis (1) and intersecting the first through hole (501);

at least one end of the optical axis (1) is provided with a baffle plate (705), the baffle plate (705) comprises a matching surface facing the optical axis (1), a third annular groove (403) and a fifth groove (305) are arranged on the matching surface, the third annular groove (403) extends along the circumferential direction of the optical axis (1), and the fifth groove (305) extends along the radial direction of the optical axis (1) and is communicated with the third annular groove (403) in a crossing way; the fifth groove (305) extends to the outer peripheral surface of the baffle plate (705), and the second through hole (502) is communicated with the third annular groove (403); the third ring groove (403) is adjacent to the optical axis (1), and the fifth groove (305) is adjacent to the magnetic steel group (2).

7. The rotor assembly according to claim 6, wherein a fourth ring groove (404) is further provided on the baffle plate (705), the fourth ring groove (404) is annularly sleeved outside the third ring groove (403), and the fourth ring groove (404) is adjacent to the magnetic steel group (2).

8. An electric machine comprising a rotor assembly as claimed in any one of claims 1 to 7.

9. A magnetic levitation blower comprising the motor of claim 8.