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 core comprise an outer magnetic pole and an inner magnetic pole, a rotating groove is formed in the surface area, opposite to the outer magnetic pole, of the thrust disc, the rotating groove extends towards the outer side from the radial inner side of the thrust disc, winding cooling flow channels are formed in the two axial stator assemblies, and the winding cooling flow channels are used for cooling windings at the corresponding positions. And the winding cooling flow channels of the two axial stator assemblies are communicated through the rotating 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 Art

[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 structural system is complex, and potential safety hazards are increased. Or in the form of negative pressure, air is sucked from the blower to guide heat out, which cannot more effectively achieve the heat dissipation of internal components, especially the heat dissipation of axial magnetic bearings is insufficient, affecting the stable operation of magnetic levitation blowers.

[0003] The axial magnetic bearing realizes the axial movement of the rotating shaft. It is essential to have an axial force-bearing component on the rotating shaft, which is the thrust disk. The materials of the axial magnetic bearing and the thrust disk are pure iron solid structures, with relatively large self-loss, general thermal conductivity, and narrow space. If not effectively cooled, they will heat up severely. 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 disk to dissipate heat from the axial magnetic bearing, but the heat dissipation efficiency is not high. Summary 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 disk 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 disk 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. Rotating grooves are formed on the surface area of the thrust disk opposite to the first outer magnetic pole and / or the second outer magnetic pole. The rotating grooves extend from the radial inner side to the outer side of the thrust disk. 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 rotating grooves.

[0006] In some embodiments, the diameter of the circle where the groove wall at the radially inner end of the rotating groove is smaller than the diameters of the radially inner annular walls of the first outer magnetic pole and the second outer magnetic pole respectively, and the radially outer end of the rotating groove penetrates through to the radially outer circle of the thrust disk.

[0007] In some embodiments, the diameter of the circle where the groove wall at the radially inner end of the rotating groove is not smaller than the diameters of the radially outer annular walls of the first inner magnetic pole and the second inner magnetic pole.

[0008] In some embodiments, a plurality of the rotating grooves are arranged at equal intervals along the circumferential direction of the thrust disk. The minimum value of the projected areas of the magnetic pole end faces of the first outer magnetic pole, the second outer magnetic pole, the first inner magnetic pole, and the second inner magnetic pole on the end face of the thrust disk is Sa, and the cross-sectional area of the magnetic path flowing through the position in the thrust disk and perpendicular to the magnetic force lines at this position is Sz, where Sz ≥ Sa.

[0009] In some embodiments, in the projection on the end face of the thrust disk, the projections of the rotating grooves on one end face of the thrust disk do not overlap with the projections of the rotating grooves on the other end face.

[0010] 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 radially outer annular wall of the first outer magnetic pole, and the second stator yoke portion has a second outer convex ring protruding from the radially outer annular 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 winding cooling channels of the first axial stator assembly and the winding cooling channels of the second axial stator assembly are communicated via the cooling cavities.

[0011] In some embodiments, the first outer magnetic pole includes a first cover plate portion extending radially inward along the thrust disk; the second outer magnetic pole includes a second cover plate portion extending radially inward along the thrust disk, and the radially extending length of the rotating groove is greater than the radial width of the first cover plate portion or the second cover plate portion.

[0012] In some embodiments, bearing exhaust holes are provided on the outer cylinder, and the bearing exhaust holes communicate with the cooling chamber and the external space of the outer cylinder; and / or, a first through hole penetrating the inner and outer sides is formed in the first stator yoke. A first annular gap is formed between the radially inner circle of the first winding and the radially outer annular wall of the first inner magnetic pole. A first flow-through 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. The first through hole, the first flow-through gap, and the first annular gap form the winding cooling flow path of the first axial stator assembly; a second through hole penetrating the inner and outer sides is formed in the second stator yoke. A second annular gap is formed between the radially inner circle of the second winding and the radially outer annular wall of the second inner magnetic pole. A second flow-through 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. The second through hole, the second flow-through gap, and the second annular gap form the winding cooling flow path of the second axial stator assembly.

[0013] In some embodiments, the rotation direction of the rotation groove is opposite to the rotation direction of the thrust disk.

[0014] The present invention also 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 impeller. The cooling air flow introduced into the magnetic levitation rotating machine by the cooling impeller and / or part of the air flow at the blower turbine can enter the axial magnetic levitation bearing through the flow-through hole and flow out of the axial magnetic levitation bearing through the winding cooling flow path.

[0015] The axial magnetic levitation bearing and the magnetic levitation rotating machine provided by the present invention have the following beneficial effects:

[0016] By forming rotation grooves on the surface areas (i.e., the left end face and the right end face) of the thrust disk opposite to the first outer magnetic pole and the second outer magnetic pole respectively, 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 flow through the axial magnetic levitation bearing, and there is a large amount of cooling fluid, achieving the purpose of efficiently cooling the thrust disk. At the same time, winding cooling flow paths are provided in each axial stator assembly and are connected to the aforementioned rotation grooves, so that the cooling fluid entering the bearing can efficiently cool the windings at the same time, thereby effectively ensuring the operation reliability of the magnetic levitation bearing. At the same time, the technical solution of the present invention is simple and easy to implement, and the manufacturing cost is relatively low. In addition, since the present invention sets rotation grooves on the end face of the rotating thrust disk, the purpose of active air suction and heat exchange of the thrust disk can also be achieved, which can further increase the flow rate of the cooling fluid entering the bearing and improve the cooling effect on the components inside the bearing. Brief Description of the Drawings

[0017] In order to more clearly illustrate the embodiments of the present invention 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 by extending the provided drawings.

[0018] Figure 1 is a schematic internal structure diagram (half-section) of an axial magnetic levitation bearing according to an embodiment of the present invention;

[0019] Figure 2 is Figure 1 a schematic diagram showing the internal circulation of the cooling air flow in the axial magnetic levitation bearing (arrow indication);

[0020] Figure 3 is Figure 1 a schematic diagram of the axial projection structure of the thrust disk in;

[0021] Figure 4 is a schematic internal structure diagram of the first embodiment of the magnetic levitation rotating machine of the present invention, and the arrows in the figure show the flow path of the cooling air flow;

[0022] Figure 5 is a schematic internal structure diagram of the second embodiment of the magnetic levitation rotating machine of the present invention, and the arrows in the figure show the flow path of the cooling air flow;

[0023] Figure 6 is a schematic internal structure diagram of the third embodiment of the magnetic levitation rotating machine of the present invention, and the arrows in the figure show the flow path of the cooling air flow;

[0024] Figure 7 A schematic internal structure diagram of the fourth embodiment of the magnetic levitation rotating machine of the present invention, and the arrows in the figure show the flow path of the cooling air flow.

[0025] The reference numerals are:

[0026] 1. Outer cylinder; 11. Bearing exhaust hole; 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 disk; 5. Rotating groove; 100. Rotating shaft; 101. Axial magnetic suspension bearing; 102. Blower turbine; 1021. Turbine volute; 1022. Front end cover; 103. Cooling impeller; 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; 1062. Stator cooling flow channel. Detailed implementation mode

[0027] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way limits the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0028] In the description of the present invention, it should be understood that the orientation terms such as "front, rear, upper, lower, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom" and other indicated orientations or position relationships are usually based on the orientations or position relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description. Without contrary explanations, these orientation terms do not indicate and imply that the devices or elements referred to must have specific orientations or be constructed and operated in specific orientations, so they cannot be understood as limiting the protection scope of the present invention; the orientation terms "inner, outer" refer to the inside and outside relative to the contours of the respective components.

[0029] For ease of description, spatial relative terms such as "above", "over", "on the upper surface", "upper" etc. can be used here to describe the spatial positional relationship of a device or feature shown in the figure with other devices or features. It should be understood that the spatial relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figure for the device. For example, if the device in the attached drawing is inverted, the device described as "above" or "over" other devices or structures will then be positioned "below" 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 the corresponding explanations are made for the spatial relative descriptions used here.

[0030] In addition, it should be noted that the use of terms such as "first", "second" etc. to define components is only for the convenience of differentiating the corresponding components. Without additional statements, the above terms have no special meanings, and thus should not be construed as limiting the protection scope of the present utility model.

[0031] Referring jointly to Figures 1 to 7 As shown, according to an embodiment of the present utility model, an axial magnetic suspension 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. A rotating groove 5 is formed on the surface area of the thrust disk 4 opposite to the first outer magnetic pole 211 and / or the second outer magnetic pole 311. The rotating groove 5 extends from the radial inner side to the outer side 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 via the rotating groove 5.

[0032] In this technical solution, by forming rotating grooves 5 on the surface areas (i.e., the left end face and the right end face) of the thrust disk 4 opposite to the first outer magnetic pole 211 and the second outer magnetic pole 311 respectively, the width of the partial air gap area between the magnetic poles and the thrust disk 4 can be increased. Furthermore, it can ensure that the cooling air flow can smoothly circulate inside 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, by arranging winding cooling channels in each axial stator assembly to communicate with the aforementioned rotating grooves 5, the cooling fluid entering the bearing can efficiently cool the windings simultaneously, thereby effectively ensuring the operation reliability of the magnetic levitation bearing. At the same time, the technical solution of the present utility model is simple and feasible, and the manufacturing cost is relatively low. In addition, since the present utility model arranges the rotating grooves 5 on the end face of the rotating thrust disk 4, it can also achieve the purpose of active air suction heat exchange of the thrust disk 4, which can further increase the flow rate of the cooling fluid entering the bearing interior and improve the cooling effect on each component inside the bearing.

[0033] In some embodiments, the diameter of the circle where the groove wall at the radially inner end of the rotating groove 5 is located is smaller than the diameters of the radially inner ring walls of the first outer magnetic pole 211 and the second outer magnetic pole 311 respectively, and the radially outer end of the rotating groove 5 penetrates through to the radially outer circle of the thrust disk 4. In this way, the rotating groove 5 can effectively ensure the communication between the radially inner side and the radially outer side of the outer magnetic pole, thereby ensuring that the cooling air flow can smoothly enter and exit the air gap space between the outer magnetic pole and the thrust disk 4, and further ensuring the efficient cooling and heat dissipation of the thrust disk 4 and the outer magnetic pole.

[0034] In some embodiments, the diameter of the circle where the groove wall at the radially inner end of the rotating groove 5 is located is not less than the diameters of the radially outer ring walls of the first inner magnetic pole 212 and the second inner magnetic pole 312, that is, the radially inner end of the rotating groove 5 does not penetrate through to the surface area of the thrust disk 4 opposite to the inner magnetic pole. The flow rate of the cooling air flow here is ensured by the winding cooling channels inside the inner magnetic pole. Furthermore, it can ensure the efficient cooling of the stator core, windings and thrust disk 4 while minimizing the area where the rotating groove 5 is opened, and thus minimizing the adverse impact on the magnetic circuit due to the opening of the rotating groove 5.

[0035] Specifically refer to Figure 3 As shown, in some embodiments, the rotating direction of the rotating groove 5 is opposite to the rotating direction of the thrust disk 4. Furthermore, the groove width of each rotating groove 5 increases from its radially inner end towards the radially outer end, that is, the rotating groove 5 is designed to be gradually wider from the inside to the outside along the radial direction of the thrust disk 4.

[0036] In some embodiments, the plurality of the rotating grooves 5 are uniformly spaced along the circumferential direction of the thrust disk 4. The minimum value of the projected area of the magnetic pole end faces of the first outer magnetic pole 211, the second outer magnetic pole 311, the first inner magnetic pole 212 and the second inner magnetic pole 312 on the end face of the thrust disk 4 is Sa, and the cross-sectional area of the position where the magnetic circuit in the thrust disk 4 flows through and is perpendicular to the magnetic force lines at this position is Sz, and Sz≥Sa. In this way, it can be ensured that the magnetic field will not saturate on the thrust disk 4 prior to the magnetic poles of the stator core, thereby minimizing the adverse effects of the formation of the rotating grooves 5 on the magnetic circuit of the magnetic field and ensuring the reliable and stable axial output force of the axial bearing.

[0037] In this way, it can be ensured that while the opening of the rotating grooves 5 meets the cooling requirements, the adverse effects on the magnetic circuit caused by the opening of the grooves can be minimized to the greatest extent.

[0038] In some embodiments, in the projection on the end face of the thrust disk 4, the projections of the rotating grooves 5 on one end face of the thrust disk 4 do not overlap with the projections of the rotating grooves 5 on the other end face, that is, the rotating grooves 5 on both end faces of the thrust disk 4 are alternately misaligned along the circumferential direction of the thrust disk 4. In this way, on the one hand, it can prevent the thickness of the thrust disk at the groove position from being too thin, resulting in a decrease in the structural strength of the thrust disk, and on the other hand, it can significantly increase the breadth of the contact position between the thrust disk 4 and the cooling air flow, further improving the cooling effect on the thrust disk 4.

[0039] 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, and 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 protruding from the radial outer ring wall of the first outer magnetic pole 211, and the second stator yoke portion 313 has a second outer convex ring 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 winding cooling channels of the first axial stator assembly 2 and the winding cooling channels of the second axial stator assembly 3 are communicated via the cooling cavity.

[0040] In this technical solution, by providing an outer convex ring radially outward along the stator yoke portion, a corresponding cooling cavity is formed between the stator core and the outer cylinder 1. At the same time, the cooling air flows in the two axial stator assemblies are communicated with this cooling cavity, so that the stator core can be cooled more efficiently and sufficiently, further preventing the temperature rise of the bearing from being too high.

[0041] In some embodiments, the outer cylinder 1 is provided with a bearing exhaust hole 11, and the bearing exhaust hole 11 communicates with the cooling cavity and the external space of the outer cylinder 1, so that the cooling air flow entering the bearing can cool and dissipate heat from the inner magnetic pole, the winding, the thrust disk 4 and the outer magnetic pole in sequence and then be discharged to the external environment.

[0042] In some embodiments, the first outer magnetic pole 211 includes a first cover plate portion 2111 extending radially inwards along the thrust disk 4; the second outer magnetic pole 311 includes a second cover plate portion 3111 extending radially inwards along the thrust disk 4, and the radial extension length of the rotating groove 5 is greater than the radial width of the first cover plate portion 2111 or the second cover plate portion 3111.

[0043] The foregoing first cover plate portion 2111 and second cover plate portion 3111 are specifically annular plates, which are part of the stator core and are used to conduct the magnetic circuit formed by the corresponding windings. Since they extend radially inwards along the thrust disk 4, the outer diameter of the corresponding thrust disk 4 can be designed to be smaller, thereby reducing the eccentric mass of the rotating shaft and being beneficial to improving the dynamic balance performance of the rotating shaft.

[0044] In some embodiments, a first through hole 2131 penetrating the inner and outer sides is formed on the first stator yoke portion 213. A first annular gap (not labeled in the figure) is formed between the radially inner circle of the first winding 22 and the radially outer annular wall of the first inner magnetic pole 212. A first flow-through 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 portion 213. The first through hole 2131, the first flow-through gap and the first annular gap form the winding cooling flow path 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 portion 313. A second annular gap (not labeled in the figure) is formed between the radially inner circle of the second winding 32 and the radially outer annular wall of the second inner magnetic pole 312. A second flow-through 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 portion 313. The second through hole 3131, the second flow-through gap and the second annular gap form the winding cooling flow path of the second axial stator assembly 3.

[0045] In this technical solution, the winding cooling flow path and the aforementioned cooling cavity are respectively located on the radial inner and outer sides of the winding, and can achieve full and efficient cooling of the radial inner and outer sides of the axial stator assembly. Since the winding cooling flow path is in communication with the rotating groove 5, the cooling of the axial magnetic suspension bearing in the present invention is more comprehensive, balanced and sufficient.

[0046] 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 levitation bearing 101 for defining the axial displacement of the rotating shaft 100. The axial magnetic levitation bearing 101 is the aforementioned axial magnetic levitation bearing. The first end of the rotating shaft 100 is connected to a blower turbine 102, and the second end of the rotating shaft 100 is connected to a cooling impeller 103. The cooling air flow introduced into the magnetic levitation rotating machine by the cooling impeller 103 and / or a part of the air flow at the blower turbine 102 can enter the axial magnetic levitation bearing through the winding cooling flow channel and flow out of the axial magnetic levitation bearing through the rotating groove 5. Thus, the pressure air flow generated by the cooling impeller 103 or the blower turbine 102 can be introduced into the axial magnetic levitation bearing to cool and dissipate heat from the components inside the bearing, effectively preventing the bearing temperature from rising too high. It should be noted that in the present invention, since the cooling impeller 103 and the blower turbine share the same rotating shaft 100, when the magnetic levitation rotating machine is operating, the rotation of the cooling impeller 103 can be synchronized, and then the external air can be introduced into the magnetic levitation rotating machine. That is, the direct drive of the cooling impeller 103 by the rotating shaft 100 is realized, without the need to separately configure a corresponding cooling structure for the cooling of the bearing, and without the need to separately set a dedicated controller for the cooling impeller 103. The control logic is simple and the heat dissipation reliability is high.

[0047] In some embodiments, the magnetic levitation rotating machine further includes a cylinder 106. An electric motor stator 105 capable of driving the rotation of the rotating shaft 100 is assembled inside the cylinder 106. A stator cooling flow channel 1062 is formed in the area of the cylinder 106 corresponding to the electric motor stator 105. At this time, the cooling air flow driven by the cooling impeller 103 can flow through the air gap between the stator and rotor of the electric motor and the stator cooling flow channel 1062, so as to cool and dissipate heat from both the inner and outer sides of the electric motor stator 105.

[0048] Figures 4 to 7 The situation where only the cooling air flow driven by the cooling impeller 103 is used to cool the components inside the magnetic levitation rotating machine is shown. The arrows in each figure indicate the flow path of the cooling air flow, and the aforementioned flow path varies according to the setting position of the exhaust hole 1061. In Figures 4 to 7 the embodiments shown in each figure, the cooling impeller 103 rotates to drive the external air flow to enter the cylinder 106 along the guide plate 1032. And Figure 4 、 Figure 5 and Figure 7Also shown is the manner in which a part of the cooling air flow is also drawn out from the blower turbine 102. That is, in a preferred embodiment, the cooling air flow is provided by the combined action of the cooling impeller 103 and the blower turbine. In this way, the introduction of the cooling air flow can be achieved from both axial ends of the magnetic levitation rotating machine, thereby ensuring comprehensive cooling of various components within the magnetic levitation rotating machine, such as the aforementioned axial magnetic levitation bearing 101, radial magnetic levitation bearing 104, and motor stator 105.

[0049] The path of the cooling air flow of the magnetic levitation rotating machine of the present invention will be further described below in conjunction with the respective figures:

[0050] First Embodiment:

[0051] See Figure 4As shown, an active pure air-cooled heat dissipation system is adopted. The cold air is provided by a cooling impeller without an additional heat dissipation drive motor. The cooling impeller 103 is assembled at the rear end of the rotor (i.e., the second end of the rotating shaft 100, the same below). The rear radial bearing (i.e., the radial magnetic levitation bearing 104 near the second end of the rotating shaft 100, the same below) is located between the cooling impeller 103 and the motor stator 105. The front radial bearing (i.e., the radial magnetic levitation bearing 104 near the first end of the rotating shaft 100, the same below) is placed at the front end of the rotor. The axial bearing (i.e., the axial magnetic levitation bearing 101, the same below) is located between the front radial bearing and the front end cover 1022. A deflector 1032 for guiding the cooling impeller and a rear end cover 1031 are assembled on the rear housing 1042 to increase the air flow conduction and reduce the flow resistance. A plurality of corresponding ventilation holes or ventilation grooves are provided on parts such as the rear housing 1042, the cylinder (i.e., the cylinder 106, the same below), and the front housing 1041 to facilitate the air flow conduction. The cooling gas of the cooling impeller passes through the flow channel on the rear housing 1042, passes through the rotor flow channel (i.e., the air gap between the stator and the rotor), cools the motor rotor, and then is divided into two paths for cooling at the front radial bearing: The first path: After entering the axial stator inner circulation channel hole and the right-side annular groove of the thrust disk or the magnetic pole on the stator (i.e., the through-flow hole and the through-flow annular groove in the second axial stator assembly), it converges with the main impeller leakage gas that has passed through the main impeller (i.e., the blower turbine 102) leakage channel (i.e., the cooling air flow diverted by the blower turbine) → the axial stator inner circulation channel hole and the left-side annular groove of the thrust disk or the magnetic pole on the stator (i.e., the through-flow hole and the through-flow annular groove in the first axial stator assembly), and then is discharged from the bearing exhaust hole 11; The second path: It cools the motor stator 105 through the motor stator flow channel outside the motor stator (i.e., the stator cooling flow channel 1062, the same below), and is discharged from the exhaust hole 1061 opened on the cylinder. This flow channel structure arrangement effectively cools the heating components such as the stator, rotor, radial bearing, and axial bearing. At the same time, for the high-heating components such as the thrust disk or the axial bearing stator, an annular groove structure is provided on the upper magnetic pole of the thrust disk or the axial bearing, and a flow channel hole is added to the inner ring of the axial bearing stator. At the high rotational speed of the rotor, the gas flow channel is increased, the cooling flow rate and speed of the introduced gas are increased, and the cooling of the axial magnetic bearing and the thrust disk is accelerated. The entire heat dissipation system has a simple structure, an efficient and reliable heat dissipation process, and improves the stability of the magnetic levitation system.

[0052] Second Embodiment:

[0053] See Figure 5As shown in the figure, an active pure air-cooled heat dissipation system is adopted. The cold air is provided by the cooling impeller without an additional heat dissipation drive motor. The cooling impeller 103 is assembled at the rear end of the rotor. The rear radial bearing is located between the cooling impeller 103 and the motor stator 105. The front radial bearing is placed at the front end of the rotor. The axial bearing is located between the front radial bearing and the motor stator 105. A deflector 1032 for guiding the cooling impeller and a rear end cover 1031 are assembled on the rear housing to increase the air flow conduction and reduce the flow resistance. A number of corresponding ventilation holes or ventilation grooves are provided on parts such as the rear housing 1042, the cylinder, and the front housing 1041 to facilitate the air flow conduction. The cooling gas of the cooling impeller is divided into three paths through the flow channel on the rear housing 1042. The first path: through the axial cooling flow channel (not labeled in the figure) in the cylinder → the axial bearing; the second path: through the motor stator flow channel on the cylinder → the axial bearing; the third path: through the motor rotor flow channel (i.e., the air gap between the motor stator and rotor) → the axial bearing; the three paths of cooling gas pass through the axial stator inner circulation channel holes and the pole or thrust disc ring grooves on the axial stator on both sides of the axial bearing and then are discharged from the bearing exhaust hole 11. This flow channel structure layout effectively cools the heat-generating components such as the stator, rotor, radial bearing, and axial bearing. At the same time, for the high-heat-generating components such as the thrust disc or the axial bearing stator, a ring groove structure is provided on the upper pole of the thrust disc or the axial bearing. Flow channel holes are added to the inner ring of the axial bearing stator. At the high rotational speed of the rotor, the gas flow channel is increased, the cooling flow rate and speed are increased, and the cooling of the axial magnetic bearing and the thrust disc is accelerated. The entire heat dissipation system has a simple structure, an efficient and reliable heat dissipation process, and improves the stability of the magnetic levitation system.

[0054] Third Embodiment:

[0055] See Figure 6As shown in the figure, an active pure air-cooling system is adopted. The cold air is provided by the cooling impeller without an additional heat dissipation drive motor. The cooling impeller 103 is assembled at the rear end of the rotor. The rear radial bearing is located between the cooling impeller 103 and the motor stator 105. The front radial bearing is placed at the front end of the rotor. The axial bearing is located between the front radial bearing and the motor stator 105. A deflector 1032 for guiding the cooling impeller and a rear end cover 1031 are assembled on the rear housing to increase the air flow conduction and reduce the flow resistance. Several corresponding ventilation holes or ventilation grooves are opened on parts such as the rear housing 1042, the cylinder body, and the front housing 1041 to facilitate the air flow conduction. The cooling gas of the cooling impeller is divided into two paths for cooling when entering the motor rotor flow channel. The first path: After cooling the motor stator through the motor stator flow channel on the cylinder body, it is discharged through the exhaust hole 1061. The second path: After passing through the axial stator inner circulation channel hole → the magnetic pole or thrust disk ring groove on the axial stator, it converges with the main impeller leakage gas passing through the main impeller leakage flow channel → the axial stator inner circulation channel hole and the magnetic pole or thrust disk ring groove on the axial stator and is discharged from the bearing exhaust hole 11. This flow channel structure layout effectively cools the heating components such as the stator, rotor, radial bearing, and axial bearing. At the same time, for the high-heating components such as the thrust disk or the axial bearing stator, a ring groove structure is provided on the magnetic pole of the thrust disk or the axial bearing, and a flow channel hole is added to the inner ring of the axial bearing stator. At the high rotational speed of the rotor, the gas flow channel is increased, the cooling flow rate and speed of the inlet are increased, and the cooling of the axial magnetic bearing and the thrust disk is accelerated. The entire heat dissipation system has a simple structure, an efficient and reliable heat dissipation process, and improves the stability of the magnetic levitation system.

[0056] Fourth Embodiment:

[0057] See Figure 7As shown in the figure, an active pure air-cooled heat dissipation system is adopted. The cold air is provided by the cooling impeller without an additional heat dissipation drive motor. The cooling impeller 103 is assembled at the rear end of the rotor. The rear radial bearing is located between the cooling impeller 103 and the motor stator 105. The front radial bearing is placed at the front end of the rotor. The axial bearing is located between the front radial bearing and the motor stator 105. A deflector 1032 for guiding the flow of the cooling impeller and a rear end cover 1031 are assembled on the rear housing to increase the air flow conduction and reduce the flow resistance. Several corresponding ventilation holes or ventilation grooves are provided on parts such as the rear housing 1042, the cylinder body, and the front housing 1041 to facilitate the air flow conduction. The cooling gas of the cooling impeller passes through the rear housing 1042, the motor stator flow channel and the motor rotor flow channel on the cylinder body, and then passes through the axial stator inner circulation channel hole and the right annular groove of the thrust disc or the magnetic pole on the stator, and then converges with the main impeller leakage gas passing through the main impeller leakage flow channel, the axial stator inner circulation channel hole and the left annular groove of the thrust disc or the magnetic pole on the axial stator, and then is discharged from the bearing exhaust hole 11. This flow channel structure arrangement effectively cools the stator, rotor, radial bearings, axial bearings and other heat-generating components. At the same time, for the high-heat-generating components such as the thrust disc or the axial bearing stator, a ring groove structure is provided on the upper magnetic pole of the thrust disc or the axial bearing, and a flow channel hole is added to the inner ring of the axial bearing stator. At the high rotational speed of the rotor, the gas flow channel is increased, the cooling flow rate and speed are increased, and the cooling of the axial magnetic bearing and the thrust disc is accelerated. The entire heat dissipation system has a simple structure, an efficient and reliable heat dissipation process, and improves the stability of the magnetic levitation system.

[0058] 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.

[0059] The above description is only a preferred embodiment of the present invention and is 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 in the protection scope of the present invention. The above description is only a 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 variations can still be made, and these improvements and variations should also be regarded as 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). A rotation groove (5) is formed on a surface area of ​​the thrust disk (4) that is opposite to the first outer magnetic pole (211) and / or the second outer magnetic pole (311). The rotation groove (5) extends from the radial inner side of the thrust disk (4) toward the outer side. Winding cooling channels are formed in both the first axial stator component (2) and the second axial stator component (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 component (2) and the second axial stator component (3) are connected via the rotation groove (5).

2. The axial magnetic bearing according to claim 1, characterized in that: The diameter of the circle where the groove wall of the radial inner end of the rotating groove (5) is located is smaller than the diameter of the radial inner ring wall of each of the first outer magnetic pole (211) and the second outer magnetic pole (311), and the radial outer end of the rotating groove (5) passes through the radial outer circle of the thrust plate (4).

3. The axial magnetic bearing according to claim 2, characterized in that: The diameter of the circle where the groove wall of the radial inner end of the rotating groove (5) is located is not less than the diameter of the radial outer ring wall of the first inner magnetic pole (212) and the second inner magnetic pole (312).

4. The axial magnetic bearing according to claim 1, characterized in that: The plurality of rotating grooves (5) are evenly spaced along the circumference of the thrust disk (4); the minimum value of the projection area of ​​the magnetic end faces of the first outer magnetic pole (211), the second outer magnetic pole (311), the first inner magnetic pole (212) and the second inner magnetic pole (312) on the end face of the thrust disk (4) is Sa; the cross-sectional area of ​​the position through which the magnetic path in the thrust disk (4) flows and which is perpendicular to the magnetic lines of force at that position is Sz, and Sz ≥ Sa.

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

6. 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 (311). 11), 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 winding 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.

7. The axial magnetic bearing according to claim 6, characterized in that: The first outer magnetic pole (211) includes a first cover plate portion (2111) extending radially inward along the thrust plate (4); the second outer magnetic pole (311) includes a second cover plate portion (3111) extending radially inward along the thrust plate (4), and the radial extension length of the rotating groove (5) is greater than the radial width of the first cover plate portion (2111) or the second cover plate portion (3111).

8. The axial magnetic bearing according to claim 7, characterized in that: The outer cylinder (1) has a bearing exhaust hole (11), and the bearing exhaust hole (11) is connected to the cooling cavity and the external space of the outer cylinder (1); and / or, the first stator yoke (213) is formed with a first through hole (2131) penetrating the inner and outer sides 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), the first through hole (2131), the first flow gap and The first annular gap forms the winding cooling channel of the first axial stator assembly (2); a second through hole (3131) penetrating the inner and outer sides of the second stator yoke (313) is formed on the second stator yoke (313); a second annular gap is formed between the radial inner circle of the second winding (32) and the radial outer ring 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).

9. The axial magnetic bearing according to claim 1, characterized in that: The rotation direction of the rotating groove (5) is opposite to the rotation direction of the thrust plate (4).

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 impeller (103), and the cooling airflow introduced into the magnetically suspended rotating machinery by the cooling impeller (103) and / or part of the airflow at the blower turbine (102) can enter the axial magnetic bearing through the winding cooling channel and flow out of the axial magnetic bearing through the rotating groove (5).

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