Axial magnetic suspension bearing and magnetic suspension rotating machine

Abstract

The utility model provides an axial magnetic suspension bearing and magnetic suspension rotating machinery, the axial magnetic suspension bearing comprises an outer cylinder, two axial stator assemblies and a thrust disc are assembled in a central through hole of the outer cylinder, each axial stator assembly comprises a stator iron core and a winding, the thrust disc is located between magnetic poles of the two stator iron cores, and the winding is arranged between the two stator iron cores. The magnetic poles of the stator iron core comprise an outer magnetic pole and an inner magnetic pole, overflowing grooves are formed in the opposite surface areas of the outer magnetic pole and the thrust disc and extend in the radial direction of the thrust disc, winding cooling flow channels are formed in the two axial stator assemblies and used for cooling the corresponding windings, and the winding cooling flow channels extend in the radial direction of the thrust disc. And the winding cooling flow channels of the axial stator assemblies are communicated through the overflowing grooves. According to the utility model, the thrust disc and the bearing winding can be effectively cooled.

Description

Technical Field

[0001] The utility model belongs to the technical field of magnetic levitation bearing design, and particularly relates to an axial magnetic levitation bearing and a magnetic levitation rotating machine. Background Technique

[0002] At present, the heat dissipation of magnetic levitation blowers mainly relies on external cooling equipment, such as external cooling fans, water cooling systems, and heat exchangers, etc. The equipment maintenance cost is high, the structure system is complex, and potential safety hazards are increased. Or in the form of negative pressure, air is sucked from the blower to guide the heat out, but it cannot more effectively achieve the heat dissipation of internal components, especially the heat dissipation of axial magnetic bearings is insufficient, which affects the stable operation of magnetic levitation blowers.

[0003] The axial magnetic bearing realizes the axial movement of the rotating shaft. It is necessary to have an axial force-bearing component on the rotating shaft, which is the thrust disc. The materials of the axial magnetic bearing and the thrust disc are pure iron solid structures, with relatively large self-loss, general thermal conductivity, and narrow space. If not effectively cooled, they will generate serious heat. Usually, in order to avoid excessive temperature rise of the axial magnetic bearing, forced air cooling is often applied externally to dissipate heat from the magnetic bearing. The cooling air is input from the outside and passes through the gap between the bearing stator and the thrust disc to dissipate heat from the axial magnetic bearing, but the heat dissipation efficiency is not high. Content of the Utility Model

[0004] Therefore, the utility model provides an axial magnetic levitation bearing and a magnetic levitation rotating machine, which can solve the technical problems of serious heating and low heat dissipation efficiency of the axial magnetic bearing in the existing magnetic levitation rotating machine.

[0005] To solve the above problems, the utility model provides an axial magnetic levitation bearing, which includes an outer cylinder. A first axial stator assembly, a second axial stator assembly, and a thrust disc are assembled in the central through hole of the outer cylinder. The first axial stator assembly includes a first stator core and a first winding assembled on the first stator core. The second axial stator assembly includes a second stator core and a second winding assembled on the second stator core. The thrust disc is located between the magnetic poles of the first stator core and the magnetic poles of the second stator core. The magnetic poles of the first stator core include a first outer magnetic pole and a first inner magnetic pole. The magnetic poles of the second stator core include a second outer magnetic pole and a second inner magnetic pole. Flow-through grooves are formed on the surface areas of the first outer magnetic pole and the thrust disc facing each other, and flow-through grooves are also formed on the surface areas of the second outer magnetic pole and the thrust disc facing each other. And the flow-through grooves extend along the radial direction of the thrust disc. Winding cooling channels are formed in both the first axial stator assembly and the second axial stator assembly. The winding cooling channels are used to cool the first winding and the second winding. And the winding cooling channels respectively provided in the first axial stator assembly and the second axial stator assembly are communicated through the flow-through grooves.

[0006] In some embodiments, when the overcurrent grooves are formed on the first outer magnetic pole and the second outer magnetic pole, the overcurrent grooves penetrate radially along the thrust disc to the respective radial inner annular walls of the first outer magnetic pole and the second outer magnetic pole, and the diameter of the circle where the radially outer end groove wall of the overcurrent groove is located is greater than the diameter of the radially outer circle of the thrust disc.

[0007] In some embodiments, a plurality of the overcurrent grooves are uniformly spaced along the circumferential direction of the thrust disc. The plane perpendicular to the rotation axis of the thrust disc is the radial plane. The projected areas of the magnetic pole end faces of the first outer magnetic pole and the second outer magnetic pole on the end face of the thrust disc are both Sa1, the projected areas of each of the overcurrent grooves on the end face of the thrust disc are both Sb1, the projected areas of the magnetic pole end faces of the first inner magnetic pole and the second inner magnetic pole on the end face of the thrust disc are both Sc1, there are n overcurrent grooves on both the first outer magnetic pole and the second outer magnetic pole, and Sa1 - nSb1 ≥ Sc1.

[0008] In some embodiments, when the overcurrent grooves are formed on the thrust disc, the overcurrent grooves penetrate radially along the thrust disc to the outer circumferential wall of the thrust disc, and the diameter of the circle where the radially inner end groove wall of the overcurrent groove is located is greater than the diameters of the radially outer circles of the first inner magnetic pole and the second inner magnetic pole.

[0009] In some embodiments, a plurality of the overcurrent grooves are uniformly spaced along the circumferential direction of the thrust disc. The plane perpendicular to the rotation axis of the thrust disc is the radial plane. The projected areas of the magnetic pole end faces of the first outer magnetic pole and the second outer magnetic pole on the end face of the thrust disc are both Sa2, the projected areas of each of the overcurrent grooves on the end face of the thrust disc are both Sb2, the projected areas of the magnetic pole end faces of the first inner magnetic pole and the second inner magnetic pole on the end face of the thrust disc are both Sc2, there are m overcurrent grooves on both the first outer magnetic pole and the second outer magnetic pole, and Sa2 - mSb2 ≥ Sc2.

[0010] In some embodiments, in the projection on the end face of the thrust disc, there is no overlapping part between the projections of the overcurrent grooves on one end face of the thrust disc and the projections of the overcurrent grooves on the other end face.

[0011] In some embodiments, the first stator core further includes a first stator yoke portion between the first outer magnetic pole and the first inner magnetic pole, and the second stator core further includes a second stator yoke portion between the second outer magnetic pole and the second inner magnetic pole. The first stator yoke portion has a first outer convex ring protruding from the radial outer ring wall of the first outer magnetic pole, and the second stator yoke portion has a second outer convex ring protruding from the radial outer ring wall of the second outer magnetic pole. The first axial stator assembly is assembled into the outer cylinder via the first outer convex ring, and the second axial stator assembly is assembled into the outer cylinder via the second outer convex ring to form cooling cavities between the first outer magnetic pole and the outer cylinder and between the second outer magnetic pole and the outer cylinder. The cooling flow channel of the first axial stator assembly and the winding cooling flow channel of the second axial stator assembly communicate with each other via the cooling cavities.

[0012] In some embodiments, the first outer magnetic pole includes a first cover plate portion extending radially inwards along the thrust disk. When the overflow groove is formed on the first outer magnetic pole, the overflow groove is formed on the first cover plate portion; the second outer magnetic pole includes a second cover plate portion extending radially inwards along the thrust disk. When the overflow groove is formed on the second outer magnetic pole, the overflow groove is formed on the second cover plate portion.

[0013] In some embodiments, a first through hole penetrating the inner and outer sides is formed on the first stator yoke portion. A first annular gap is formed between the radial inner circle of the first winding and the radial outer ring wall of the first inner magnetic pole. A first overflow gap is formed between the end face of the first winding away from the first cover plate portion and the inner end face of the first stator yoke portion. The first through hole, the first overflow gap and the first annular gap form the winding cooling flow channel of the first axial stator assembly; a second through hole penetrating the inner and outer sides is formed on the second stator yoke portion. A second annular gap is formed between the radial inner circle of the second winding and the radial outer ring wall of the second inner magnetic pole. A second overflow gap is formed between the end face of the second winding away from the second cover plate portion and the inner end face of the second stator yoke portion. The second through hole, the second overflow gap and the second annular gap form the winding cooling flow channel of the second axial stator assembly.

[0014] The present utility model further provides a magnetic levitation rotating machine, including a rotating shaft and an axial magnetic levitation bearing for defining the axial displacement of the rotating shaft. The axial magnetic levitation bearing is the above-mentioned axial magnetic levitation bearing. The first end of the rotating shaft is connected to a blower turbine, and the second end of the rotating shaft is connected to a cooling air blade. The cooling air flow introduced into the magnetic levitation rotating machine by the cooling air blade and / or a part of the air flow at the blower turbine can enter the axial magnetic levitation bearing via the cooling flow channel.

[0015] The axial magnetic suspension bearing and the magnetic suspension rotating machine provided by the utility model have the following beneficial effects:

[0016] By forming overcurrent grooves on the surface areas where the first outer magnetic pole and the thrust disk face each other and on the surface areas where the second outer magnetic pole and the thrust disk face each other, the width of the partial air gap area between the magnetic poles and the thrust disk can be increased. Furthermore, it can ensure that the cooling air flow can smoothly circulate inside the axial magnetic suspension bearing and has a large amount of cooling fluid, achieving the purpose of efficiently cooling the thrust disk. At the same time, by arranging winding cooling channels in each axial stator assembly to communicate with the aforementioned overcurrent grooves, the cooling fluid entering the bearing can efficiently cool the windings at the same time, thereby effectively ensuring the operation reliability of the magnetic suspension bearing. At the same time, the technical solution of the utility model is simple, feasible, and has a low manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. The drawings in the following description are only exemplary. For those of ordinary skill in the art, without creative efforts, other implementation drawings can also be obtained based on the provided drawings.

[0018] Figure 1 is a perspective structural schematic diagram (sectional view) of the axial magnetic suspension bearing according to an embodiment of the present utility model, in which the overcurrent groove is formed on the outer magnetic pole of the stator core;

[0019] Figure 2 is Figure 1 the front view (half-section) of the axial magnetic suspension bearing in;

[0020] Figure 3 is Figure 1 the axial projection view of the cover plate part of the stator core in;

[0021] Figure 4 is the front view (half-section) of the axial magnetic suspension bearing according to another embodiment of the present utility model, in which the overcurrent groove is formed on the two end faces of the thrust disk;

[0022] Figure 5 is Figure 4 the perspective structural schematic diagram (sectional view) of the axial magnetic suspension bearing in;

[0023] Figure 6 is Figure 4 the axial projection view of the thrust disk in;

[0024] Figure 7 is the internal structural schematic diagram of the first embodiment of the magnetic suspension rotating machine of the present utility model, in which Figure 1The axial magnetic suspension bearing in [reference], and the arrows in the figure show the flow path of the cooling air flow;

[0025] Figure 8 is a schematic diagram of the internal structure of the second embodiment of the magnetic suspension rotating machine of the present invention. In the figure, Figure 1 The axial magnetic suspension bearing in [reference], and the arrows in the figure show the flow path of the cooling air flow;

[0026] Figure 9 is a schematic diagram of the internal structure of the third embodiment of the magnetic suspension rotating machine of the present invention. In the figure, Figure 1 The axial magnetic suspension bearing in [reference], and the arrows in the figure show the flow path of the cooling air flow;

[0027] Figure 10 Schematic diagram of the internal structure of the fourth embodiment of the magnetic suspension rotating machine of the present invention. In the figure, Figure 4 The axial magnetic suspension bearing in [reference], and the arrows in the figure show the flow path of the cooling air flow;

[0028] Figure 11 is a schematic diagram of the internal structure of the fifth embodiment of the magnetic suspension rotating machine of the present invention. In the figure, Figure 4 The axial magnetic suspension bearing in [reference], and the arrows in the figure show the flow path of the cooling air flow;

[0029] Figure 12 is a schematic diagram of the internal structure of the sixth embodiment of the magnetic suspension rotating machine of the present invention. In the figure, Figure 4 The axial magnetic suspension bearing in [reference], and the arrows in the figure show the flow path of the cooling air flow;

[0030] Figure 13 is a schematic diagram of the internal structure of the seventh embodiment of the magnetic suspension rotating machine of the present invention. In the figure, Figure 4 The axial magnetic suspension bearing in [reference], and the arrows in the figure show the flow path of the cooling air flow;

[0031] Figure 14 is a schematic diagram of the internal structure of the eighth embodiment of the magnetic suspension rotating machine of the present invention. In the figure, Figure 1 The axial magnetic suspension bearing in [reference], and the arrows in the figure show the flow path of the cooling air flow;

[0032] Figure 15 is a schematic diagram of the internal structure of the ninth embodiment of the magnetic suspension rotating machine of the present invention. In the figure, Figure 4 The axial magnetic suspension bearing in [reference], and the arrows in the figure show the flow path of the cooling air flow;

[0033] Figure 16 is a schematic diagram of the internal structure of the tenth embodiment of the magnetic suspension rotating machine of the present invention. In the figure,Figure 1 The axial magnetic suspension bearing in [reference], and the arrows in the figure show the flow path of the cooling air flow;

[0034] Figure 17 It is a schematic diagram of the internal structure of the eleventh embodiment of the magnetic suspension rotating machine of the present utility model. In the figure, Figure 1 the axial magnetic suspension bearing in [reference] is adopted, and the arrows in the figure show the flow path of the cooling air flow;

[0035] Figure 18 It is a schematic diagram of the internal structure of the twelfth embodiment of the magnetic suspension rotating machine of the present utility model. In the figure, Figure 4 the axial magnetic suspension bearing in [reference] is adopted, and the arrows in the figure show the flow path of the cooling air flow;

[0036] Figure 19 It is a schematic diagram of the internal structure of the thirteenth embodiment of the magnetic suspension rotating machine of the present utility model. In the figure, Figure 4 the axial magnetic suspension bearing in [reference] is adopted, and the arrows in the figure show the flow path of the cooling air flow.

[0037] The reference numerals are:

[0038] 1. Outer cylinder; 2. First axial stator assembly; 21. First stator core; 211. First outer magnetic pole; 2111. First cover part; 212. First inner magnetic pole; 213. First stator yoke; 2131. First through hole; 22. First winding; 3. Second axial stator assembly; 31. Second stator core; 311. Second outer magnetic pole; 3111. Second cover part; 312. Second inner magnetic pole; 313. Second stator yoke; 3131. Second through hole; 32. Second winding; 4. Thrust disc; 5. Flow-through groove; 100. Rotating shaft; 1001. Air guiding channel; 101. Axial magnetic suspension bearing; 102. Blower turbine; 1021. Turbine volute; 1022. Front end cover; 103. Cooling air blade; 1031. Rear end cover; 1032. Deflector; 104. Radial magnetic suspension bearing; 1041. Front housing; 1042. Rear housing; 105. Motor stator; 106. Cylinder; 1061. Exhaust hole. Detailed implementation manners

[0039] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way limits the present utility model and its application or use. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present utility model.

[0040] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom", etc. is usually based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description. Without contrary description, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the protection scope of the present utility model; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0041] For the convenience of description, spatial relative terms such as "above...", "over...", "on the upper surface of...", "above-mentioned", etc. can be used here to describe the spatial positional relationship between a device or feature shown in the drawings and other devices or features. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation described in the drawings for the device. For example, if the device in the drawing is inverted, the device described as "above other devices or structures" or "over other devices or structures" will then be positioned as "below other devices or structures" or "under other devices or structures". Thus, the exemplary term "above..." can include both the orientations of "above..." and "below...". The device can also be positioned in other different ways (rotated 90° or in other orientations), and corresponding interpretations should be made for the spatial relative descriptions used here.

[0042] In addition, it should be noted that the use of words such as "first", "second", etc. to limit components is only for the convenience of distinguishing the corresponding components. Without additional declaration, the above-mentioned words have no special meaning. Therefore, it cannot be understood as a limitation on the protection scope of the present utility model.

[0043] See in combination with Figures 1 to 19As shown, according to an embodiment of the present invention, an axial magnetic levitation bearing is provided, which includes an outer cylinder 1 (in some cases, the outer cylinder 1 can be the cylinder 106 hereinafter). A first axial stator assembly 2, a second axial stator assembly 3, and a thrust disk 4 are assembled in the central through hole of the outer cylinder 1. The first axial stator assembly 2 includes a first stator core 21 and a first winding 22 assembled on the first stator core 21. The second axial stator assembly 3 includes a second stator core 31 and a second winding 32 assembled on the second stator core 31. The thrust disk 4 is located between the magnetic poles of the first stator core 21 and the magnetic poles of the second stator core 31, and corresponding air gaps are respectively formed between the thrust disk 4 and the first stator core 21 and between the thrust disk 4 and the second stator core 31. The magnetic poles of the first stator core 21 include a first outer magnetic pole 211 and a first inner magnetic pole 212. The magnetic poles of the second stator core 31 include a second outer magnetic pole 311 and a second inner magnetic pole 312. Current-carrying grooves 5 are formed on the surface areas of the first outer magnetic pole 211 and the thrust disk 4 facing each other and on the surface areas of the second outer magnetic pole 311 and the thrust disk 4 facing each other. It can be understood that the current-carrying grooves 5 can be independently formed on the magnetic pole end faces of the first outer magnetic pole 211 or the second outer magnetic pole 311 or on both end faces of the thrust disk 4, or can be formed on the aforementioned end faces simultaneously. And the current-carrying grooves 5 extend along the radial direction of the thrust disk 4. Winding cooling channels (not labeled in the figure) are formed in both the first axial stator assembly 2 and the second axial stator assembly 3. The winding cooling channels are used to cool the first winding 22 and the second winding 32, and the winding cooling channels respectively provided in the first axial stator assembly 2 and the second axial stator assembly 3 are communicated through the current-carrying grooves 5.

[0044] In this technical solution, by forming the current-carrying grooves 5 on the surface areas of the first outer magnetic pole 211 and the thrust disk 4 facing each other and on the surface areas of the second outer magnetic pole 311 and the thrust disk 4 facing each other, the width of some air gap areas between the magnetic poles and the thrust disk 4 can be increased. Furthermore, it can be ensured that the cooling air flow can smoothly flow through the inside of the axial magnetic levitation bearing, and there is a large amount of cooling fluid, achieving the purpose of efficiently cooling the thrust disk 4. At the same time, winding cooling channels are provided in each axial stator assembly and are communicated with the aforementioned current-carrying grooves 5, so that the cooling fluid entering the bearing can efficiently cool the windings at the same time. Furthermore, the operation reliability of the magnetic levitation bearing is effectively ensured. At the same time, the technical solution of the present invention is simple and easy to implement, and the manufacturing cost is relatively low.

[0045] Specifically refer to Figures 1 to 3As shown, when the overcurrent groove 5 is formed on the first outer magnetic pole 211 and the second outer magnetic pole 311, the overcurrent groove 5 penetrates along the radial direction of the thrust disk 4 to the respective radial inner ring walls of the first outer magnetic pole 211 and the second outer magnetic pole 311, and the diameter of the circle where the radially outer end groove wall of the overcurrent groove 5 is located is greater than the radially outer circle diameter of the thrust disk 4. In this way, it can ensure that the cooling fluid flowing out of the aforementioned winding cooling channel smoothly flows out through the overcurrent groove 5 on one side of the stator core. At the same time, it can also ensure that the cooling air flowing out of the winding cooling channel on one side smoothly enters the winding cooling channel on the other side, thereby improving the cooling effect on the windings in the axial stator cores on both sides.

[0046] In some embodiments, a plurality of the overcurrent grooves 5 are evenly spaced along the circumferential direction of the thrust disk 4. Any plane perpendicular to the rotation axis of the thrust disk 4 is a radial plane. The projected areas of the magnetic pole end faces of the first outer magnetic pole 211 and the second outer magnetic pole 311 on the end face of the thrust disk 4 (that is, the projected area within the range where the magnetic pole end face and the end face of the thrust disk 4 face each other, rather than the projected area of the entire magnetic pole end face) are both Sa1. The projected areas of the end faces of each of the overcurrent grooves 5 on the end face of the thrust disk 4 are both Sb1. The projected areas of the magnetic pole end faces of the first inner magnetic pole 212 and the second inner magnetic pole 312 on the end face of the thrust disk 4 are both Sc1. There are n overcurrent grooves 5 on both the first outer magnetic pole 211 and the second outer magnetic pole 311, and Sa1 - nSb1 ≥ Sc1. In this way, it can ensure that the opening of the overcurrent groove 5 meets the cooling requirements while minimizing the adverse effects on the magnetic field caused by the opening of the groove. In a specific embodiment, n = 4.

[0047] In some embodiments, when the overcurrent groove 5 is formed on the thrust disk 4, the overcurrent groove 5 penetrates along the radial direction of the thrust disk 4 to the outer circumferential wall of the thrust disk 4, and the diameter of the circle where the radially inner end groove wall of the overcurrent groove 5 is located is greater than the radially outer circle diameters of the first inner magnetic pole 212 and the second inner magnetic pole 312. Objectively speaking, the overcurrent groove 5 in the present invention is only formed in the outer circular ring area of the thrust disk 4, and it does not penetrate the entire radial area from the radial inner side to the outer side of the thrust disk 4. That is, the overcurrent groove 5 is not provided in the area of the thrust disk 4 opposite to the first inner magnetic pole 212, and the overcurrent groove 5 is not provided in the area of the thrust disk 4 opposite to the second inner magnetic pole 312. The overcurrent groove 5 is only provided at its corresponding positions with the first outer magnetic pole 211 and the second outer magnetic pole 311. In this way, it can minimize the occurrence of overheating phenomena caused by eddy currents generated by the alternating magnetic field generated during the rotation of the thrust disk 4.

[0048] In some embodiments, a plurality of the overcurrent grooves 5 are uniformly spaced along the circumferential direction of the thrust disc 4. A plane perpendicular to the rotation axis of the thrust disc 4 is a radial plane. The projected areas of the magnetic pole end faces of the first outer magnetic pole 211 and the second outer magnetic pole 311 on the end face of the thrust disc 4 are both Sa2. The projected areas of each of the overcurrent grooves 5 on the end face of the thrust disc 4 are all Sb2. The projected areas of the magnetic pole end faces of the first inner magnetic pole 212 and the second inner magnetic pole 312 on the end face of the thrust disc 4 are both Sc2. The projected areas of the two side end faces of the thrust disc 4 on the end face of the thrust disc 4 are both Sd. Both the first outer magnetic pole 211 and the second outer magnetic pole 311 have m of the overcurrent grooves 5, and Sa2 - mSb2 ≥ Sc2. In this way, while ensuring that the opening of the overcurrent grooves 5 meets the cooling requirements, it is also possible to minimize the adverse effects on the magnetic field caused by the opening of the grooves to the greatest extent.

[0049] In some embodiments, in the projection on the end face of the thrust disc 4, the projections of the overcurrent grooves 5 on one end face of the thrust disc 4 do not overlap with the projections of the overcurrent grooves 5 on the other end face. That is, the overcurrent grooves 5 on the two side end faces of the thrust disc 4 are alternately offset along the circumferential direction of the thrust disc 4. On the one hand, this can prevent the thickness at the groove position of the thrust disc 4 from being too thin, resulting in a decrease in the structural strength of the thrust disc. On the other hand, it can significantly increase the breadth of the contact position between the thrust disc 4 and the cooling air flow, further improving the cooling effect on the thrust disc.

[0050] In some embodiments, the first stator core 21 further includes a first stator yoke portion 213 between the first outer magnetic pole 211 and the first inner magnetic pole 212. The second stator core 31 further includes a second stator yoke portion 313 between the second outer magnetic pole 311 and the second inner magnetic pole 312. The first stator yoke portion 213 has a first outer convex ring (not labeled in the figure) protruding from the radial outer ring wall of the first outer magnetic pole 211. The second stator yoke portion 313 has a second outer convex ring (not labeled in the figure) protruding from the radial outer ring wall of the second outer magnetic pole 311. The first axial stator assembly 2 is assembled into the outer cylinder 1 via the first outer convex ring, and the second axial stator assembly 3 is assembled into the outer cylinder 1 via the second outer convex ring to form a cooling cavity (not labeled in the figure) between the first outer magnetic pole 211 and the outer cylinder 1 and between the second outer magnetic pole 311 and the outer cylinder 1. The cooling flow channel of the first axial stator assembly 2 and the winding cooling flow channel of the second axial stator assembly 3 are communicated via the cooling cavity.

[0051] In this technical solution, an outwardly convex ring is arranged on the stator yoke along its radial direction, so that a corresponding cooling cavity is formed between the stator core and the outer cylinder 1. At the same time, the winding cooling channels in the axial stator assemblies on both sides are communicated with this cooling cavity, so that the stator core can be cooled more efficiently and sufficiently, and further prevent the temperature rise of the bearing from being too high.

[0052] In some embodiments, the first outer magnetic pole 211 includes a first cover plate portion 2111 extending radially inwards along the thrust disk 4. When the overflow groove 5 is formed on the first outer magnetic pole 211, the overflow groove 5 is formed on the first cover plate portion 2111 (as Figure 3 shown); the second outer magnetic pole 311 includes a second cover plate portion 3111 extending radially inwards along the thrust disk 4. When the overflow groove 5 is formed on the second outer magnetic pole 311, the overflow groove 5 is formed on the second cover plate portion 3111 (as Figure 3 shown).

[0053] The aforementioned first cover plate portion 2111 and second cover plate portion 3111 are specifically both an annular plate, which is used as a part of the stator core to conduct the magnetic circuit formed by the corresponding windings. Since it extends radially inwards along the thrust disk 4, the outer diameter of the corresponding thrust disk 4 can be designed to be smaller, so as to reduce the eccentric mass of the rotating shaft and is beneficial to improving the dynamic balance performance of the rotating shaft.

[0054] In some embodiments, a first through hole 2131 penetrating the inner and outer sides is formed on the first stator yoke 213. A first annular gap (not labeled in the figure) is formed between the radial inner circle of the first winding 22 and the radial outer wall of the first inner magnetic pole 212. A first overflow gap (not labeled in the figure) is formed between the end face of the first winding 22 far from the first cover plate portion 2111 and the inner end face of the first stator yoke 213. The first through hole 2131, the first overflow gap and the first annular gap form the winding cooling channel of the first axial stator assembly 2; a second through hole 3131 penetrating the inner and outer sides is formed on the second stator yoke 313. A second annular gap (not labeled in the figure) is formed between the radial inner circle of the second winding 32 and the radial outer wall of the second inner magnetic pole 312. A second overflow gap (not labeled in the figure) is formed between the end face of the second winding 32 far from the second cover plate portion 3111 and the inner end face of the second stator yoke 313. The second through hole 3131, the second overflow gap and the second annular gap form the winding cooling channel of the second axial stator assembly 3.

[0055] In this technical solution, the winding cooling flow channel and the aforementioned cooling cavity are respectively located on the inner and outer sides of the winding in the radial direction, which can achieve full and efficient cooling of the inner and outer sides of the axial stator assembly in the radial direction. Since the winding cooling flow channel is in communication with the flow-through groove 5, the cooling of the axial magnetic bearing in the present invention is more comprehensive, balanced and sufficient.

[0056] According to an embodiment of the present invention, there is also provided a magnetic levitation rotating machine, such as a blower, an air compressor, etc., including a rotating shaft 100 and an axial magnetic bearing 101 for defining the axial displacement of the rotating shaft 100. The axial magnetic bearing 101 is the aforementioned axial magnetic bearing. Refer to Figure 14 As shown, in another embodiment, the first end of the rotating shaft 100 is connected to a blower turbine. The rotating shaft 100 has an air guiding channel 1001 extending from the end face of its second end towards the first end. The cooling air flow is introduced into the air guiding channel 1001 by the rotating shaft 100 relying on centrifugal force during rotation. Specifically, a corresponding air guiding structure is provided in the air guiding channel 1001 of the rotating shaft 100. When the rotating shaft 100 rotates at a high speed, the external air is introduced axially inward along the rotating shaft 100 under the action of the air guiding structure in the air guiding channel 1001 and flows out from the radial through holes (not marked in the figure) on the rotating shaft 100 and is sent into the magnetic levitation rotating machine to achieve cooling of various components in the magnetic levitation rotating machine. Further refer to Figure 14 As shown, the radial through holes of the air guiding channel 1001 are located between the axial magnetic bearing 101 and the motor stator 105, and the exhaust holes 1061 are respectively arranged at the front end position and the rear end position of the cylinder 106, thereby ensuring full and efficient cooling of all relevant components in the axial direction of the rotating shaft 100.

[0057] Specifically, the cooling air flow cools the motor stator 105 (and the motor rotor), the radial magnetic suspension bearing 104, and the axial magnetic suspension bearing 101 inside the cylinder 106. Exhaust holes 1061 penetrating the inside and outside of the cylinder 106 are formed on the cylinder 106. Part of the exhaust holes 1061 are formed in the front end area of the cylinder 106, and part of the exhaust holes 1061 are formed in the rear end area of the cylinder 106. The external pressure cooling air flow is introduced into the cylinder 106 through the air guiding channel 1001. One part flows through the cooling channel between the motor stator 105, the cylinder 106, and the rotating shaft 100 under the action of the pressure difference to cool the motor stator 105 and then is discharged through the exhaust holes 1061 in the rear end area. The other part enters the interior of the axial magnetic suspension bearing from the winding cooling flow channel in the second axial stator assembly 3 near the outlet of the air guiding channel 1001 under the action of the pressure difference, and successively passes through the flow-through grooves on the right side, the cooling cavity, the flow-through grooves on the left side, and then enters the winding cooling flow channel in the first axial stator assembly 2 on the left side to fully and comprehensively cool each component inside the bearing, and finally is discharged outside the cylinder through the exhaust holes 1061 in the front end area. Figure 15 The cooling principle in Figure 14 is the same as that of the magnetic suspension rotating machine in

[0058] and will not be elaborated here. Figures 7 to 13 、 Figures 16 to 19 As a preferred embodiment, as shown in

[0059] Figures 7 to 13 the present invention also provides a magnetic suspension rotating machine, including a rotating shaft 100 and an axial magnetic suspension bearing 101 for defining the axial displacement of the rotating shaft 100. The axial magnetic suspension bearing 101 is the above-mentioned axial magnetic suspension bearing. The first end of the rotating shaft 100 is connected to the blower turbine 102, and the second end of the rotating shaft 100 is connected to the cooling fan blade 103. The cooling air flow introduced into the magnetic suspension rotating machine by the cooling fan blade 103 and / or part of the air flow at the blower turbine 102 can enter the axial magnetic suspension bearing through the cooling flow channel. In this way, by arranging the cooling fan blade 103 at one end of the rotating shaft 100, the self-driving of the cooling air flow can be realized, and there is no need to separately configure corresponding driving components for the cooling air flow outside the magnetic suspension rotating machine, reducing the manufacturing and maintenance costs of the equipment and simplifying the structural design. At the same time, part of the air flow at the composite diversion blower turbine 102 is used to dissipate heat from the axial magnetic suspension bearing, further improving the heat dissipation effect and reducing the bearing temperature rise.The magnetic levitation rotating machines shown all use the cooling fan 103 as the driving source of the cooling air flow. When the rotating shaft 100 is driven to rotate, it drives the cooling fan 103 to rotate synchronously, and then drives the external air flow to enter the cylinder body 106 along the guiding direction of the guide plate 1032, flows axially along the rotating shaft 100 into the axial magnetic levitation bearing 101 and finally discharges from the exhaust hole 1061 in the front end area of the cylinder body 106, completing the overall heat dissipation of the magnetic levitation rotating machine. Different settings of the position of the exhaust hole 1061 will result in different flow paths of the cooling air flow. For details, please refer to Figures 7 to 13 the schematic illustration of each arrow in

[0060] Figures 16 to 19 which shows the case where the magnetic levitation rotating machine uses the cooling air flow of the cooling fan 103 and also extracts part of the pressurized gas from the blower turbine 102 as the cooling air flow. At this time, the flow path of the cooling air flow is determined according to the air pressure difference at both ends of the rotating shaft and the specific setting position of the exhaust hole 1061. Since the air flows from both the cooling fan 103 and the blower turbine 102 are used to cool the components in the magnetic levitation rotating machine, the cooling effect is better and the operation of the magnetic levitation rotating machine is more reliable and stable.

[0061] It is easy for those skilled in the art to understand that, on the premise of no conflict, the advantageous technical features of the above-mentioned various methods can be freely combined and superimposed.

[0062] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention. The above is only the preferred implementation manner of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and modifications can still be made, and these improvements and modifications should also be regarded as within the protection scope of the present invention.

Claims

1. An axial magnetic bearing, comprising an outer cylinder (1), wherein a first axial stator assembly (2), a second axial stator assembly (3) and a thrust plate (4) are assembled in a central through hole of the outer cylinder (1), wherein the first axial stator assembly (2) comprises a first stator core (21) and a first winding (22) assembled on the first stator core (21), and the second axial stator assembly (3) comprises a second stator core (31) and a second winding (32) assembled on the second stator core (31), and the thrust plate (4) is located between the magnetic poles of the first stator core (21) and the magnetic poles of the second stator core (31), and characterized in that: The magnetic poles of the first stator core (21) include a first outer magnetic pole (211) and a first inner magnetic pole (212), and the magnetic poles of the second stator core (31) include a second outer magnetic pole (311) and a second inner magnetic pole (312). An overflow groove (5) is formed on the surface area where the first outer magnetic pole (211) and the thrust disk (4) are opposite to each other, and an overflow groove (5) is also formed on the surface area where the second outer magnetic pole (311) and the thrust disk (4) are opposite to each other, and the overflow groove (5) extends radially along the thrust disk (4). Winding cooling channels are formed in the first axial stator component (2) and the second axial stator component (3), and the winding cooling channels are used to cool the first winding (22) and the second winding (32), and the winding cooling channels respectively provided in the first axial stator component (2) and the second axial stator component (3) are connected via the overflow groove (5).

2. The axial magnetic bearing according to claim 1, characterized in that: When the flow groove (5) is formed on the first outer magnetic pole (211) and the second outer magnetic pole (311), the flow groove (5) penetrates along the radial direction of the thrust plate (4) to the radial inner ring wall of each of the first outer magnetic pole (211) and the second outer magnetic pole (311), and the diameter of the circle where the radial outer end groove wall of the flow groove (5) is located is greater than the radial outer circle diameter of the thrust plate (4).

3. The axial magnetic bearing according to claim 2, characterized in that: A plurality of the flow grooves (5) are evenly spaced along the circumference of the thrust disk (4); the projection areas of the magnetic end faces of the first outer magnetic pole (211) and the second outer magnetic pole (311) on the end face of the thrust disk (4) are both Sa1; the projection areas of the flow grooves (5) on the end face of the thrust disk (4) are both Sb1; the projection areas of the magnetic end faces of the first inner magnetic pole (212) and the second inner magnetic pole (312) on the end face of the thrust disk (4) are both Sc1; the first outer magnetic pole (211) and the second outer magnetic pole (311) are both provided with n flow grooves (5); Sa1-nSb1≥Sc1.

4. The axial magnetic bearing according to claim 1, characterized in that: When the flow groove (5) is formed on the thrust disk (4), the flow groove (5) penetrates the thrust disk (4) in the radial direction to the outer circumferential wall of the thrust disk (4), and the diameter of the circle where the radial inner end groove wall of the flow groove (5) is located is greater than the radial outer diameter of the first inner magnetic pole (212) and the second inner magnetic pole (312).

5. The axial magnetic bearing according to claim 4, characterized in that: A plurality of the flow grooves (5) are evenly spaced along the circumference of the thrust disk (4); the projection areas of the magnetic end faces of the first outer magnetic pole (211) and the second outer magnetic pole (311) on the end face of the thrust disk (4) are both Sa2; the projection areas of the flow grooves (5) on the end face of the thrust disk (4) are both Sb2; the projection areas of the magnetic end faces of the first inner magnetic pole (212) and the second inner magnetic pole (312) on the end face of the thrust disk (4) are both Sc2; the first outer magnetic pole (211) and the second outer magnetic pole (311) are both provided with m flow grooves (5); Sa2-mSb2≥Sc2.

6. The axial magnetic bearing according to claim 5, characterized in that: In the projection on the end surface of the thrust plate (4), the projection of each flow groove (5) on one end surface of the thrust plate (4) has no overlapping part with the projection of each flow groove (5) on the other end surface.

7. The axial magnetic bearing according to claim 1, characterized in that: The first stator core (21) further comprises a first stator yoke (213) located between the first outer magnetic pole (211) and the first inner magnetic pole (212); the second stator core (31) further comprises a second stator yoke (313) located between the second outer magnetic pole (311) and the second inner magnetic pole (312); the first stator yoke (213) comprises a first outer protruding ring protruding from a radial outer ring wall of the first outer magnetic pole (211); and the second stator yoke (313) comprises a first outer protruding ring protruding from a radial outer ring wall of the second outer magnetic pole (211). The first axial stator component (2) is assembled in the outer cylinder (1) via the first outer convex ring, and the second axial stator component (3) is assembled in the outer cylinder (1) via the second outer convex ring to form a cooling cavity between the first outer magnetic pole (211) and the outer cylinder (1) and between the second outer magnetic pole (311) and the outer cylinder (1), and the cooling channel of the first axial stator component (2) and the winding cooling channel of the second axial stator component (3) are connected via the cooling cavity.

8. The axial magnetic bearing according to claim 7, characterized in that: The first outer magnetic pole (211) includes a first cover plate portion (2111) extending radially inward along the thrust disk (4), and when the flow groove (5) is formed on the first outer magnetic pole (211), the flow groove (5) is formed on the first cover plate portion (2111); the second outer magnetic pole (311) includes a second cover plate portion (3111) extending radially inward along the thrust disk (4), and when the flow groove (5) is formed on the second outer magnetic pole (311), the flow groove (5) is formed on the second cover plate portion (3111).

9. The axial magnetic bearing according to claim 8, characterized in that: The first stator yoke (213) is formed with a first through hole (2131) penetrating the inside and outside thereof, a first annular gap is formed between the radial inner circle of the first winding (22) and the radial outer annular wall of the first inner magnetic pole (212), a first flow gap is formed between the end surface of the first winding (22) away from the first cover plate (2111) and the inner end surface of the first stator yoke (213), and the first through hole (2131), the first flow gap and the first annular gap form the winding cooling flow channel of the first axial stator assembly (2); The second stator yoke (313) is provided with a second through hole (3131) penetrating the inner and outer sides thereof; a second annular gap is formed between the radial inner circle of the second winding (32) and the radial outer annular wall of the second inner magnetic pole (312); a second flow gap is formed between the end surface of the second winding (32) away from the second cover plate (3111) and the inner end surface of the second stator yoke (313); the second through hole (3131), the second flow gap and the second annular gap form the winding cooling channel of the second axial stator assembly (3).

10. A magnetically suspended rotating machine, comprising a rotating shaft (100) and an axial magnetically suspended bearing (101) for limiting the axial displacement of the rotating shaft (100), characterized in that: The axial magnetic bearing (101) is an axial magnetic bearing according to any one of claims 1 to 9, the first end of the rotating shaft (100) is connected to the blower turbine (102), and the second end of the rotating shaft (100) is connected to the cooling fan blade (103), and the cooling fan blade (103) introduces a cooling air flow into the magnetically suspended rotating machine and / or part of the air flow at the blower turbine (102) can enter the axial magnetic bearing through the cooling flow channel.

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