Stator and motor

Abstract

The invention provides a stator, the stator is applied to a radial magnetic suspension bearing, the stator is provided with a shaft hole for inserting a rotor, the stator comprises a plurality of pole columns surrounding the rotor, the pole columns are provided with windings, the first ends of the pole columns face the rotor, an air gap is formed between the first ends of the pole columns and the rotor, and the second ends of the pole columns face the rotor. And the plurality of pole columns can move along the axial directions of the pole columns at the same time to change the size of the air gap, so that the technical problem of low universality of the stator of the magnetic suspension bearing in the prior art can be solved.

Description

Technical Field

[0001] The invention belongs to the technical field of motors, and in particular relates to a stator and a motor. Background Art

[0002] Magnetic bearings are bearings that use electric and magnetic field forces to suspend the shaft. They have the advantages of no contact, no wear, high speed, high precision, no need for lubrication and sealing, etc. Magnetic bearings can be divided into three categories according to their working principles: active magnetic bearings, passive magnetic bearings and hybrid magnetic bearings. Active magnetic bearings use controllable electromagnetic forces to suspend the rotating shaft, and have the advantages that the rotor position, bearing stiffness and damping can be determined by the control system. Hybrid magnetic bearings are a combined magnetic bearing system formed on the basis of active magnetic bearings, passive magnetic bearings and some other auxiliary supports and stable structures. It uses the magnetic field generated by permanent magnets to replace the static bias magnetic field of electromagnets. Hybrid magnetic bearings have the advantages of small size, light weight and high efficiency, and are suitable for miniaturized and small applications. The mechanical part of the magnetic bearing system is generally composed of radial bearings and axial bearings, and the radial bearing is composed of a stator and a rotor. At present, due to the different rotor sizes between compressors of different models, stators with different inner diameters need to be matched, and the universality is not high.

[0003] How to improve the universality of the stator of the magnetic bearing is a technical problem that urgently needs to be solved. Summary of the invention

[0004] Therefore, the present invention provides a stator and a motor, which can solve the technical problem of low versatility of the stator of the magnetic bearing in the prior art.

[0005] The present invention provides a stator, which is applied to a radial magnetic bearing. The stator is provided with an axial hole for inserting a rotor. The stator includes a plurality of poles surrounding the rotor, a winding is provided on the pole, a first end of the pole faces the rotor and an air gap is formed between the pole and the rotor, and the plurality of poles can move simultaneously along their own axial direction to change the size of the air gap.

[0006] In some embodiments, the stator includes a yoke, the yoke is provided with an annular groove opening toward the shaft hole, the second end of the pole is connected to a support column, and the support column is movably disposed in the annular groove.

[0007] In some embodiments, a threaded hole is provided at one end of the support column away from the pole, and a threaded rod is provided through the bottom surface of the annular groove. The threaded rod is adapted to the threaded hole, and rotation of the threaded rod can drive the support column to approach or move away from the axial hole.

[0008] In some embodiments, the stator further includes a rotation member, and the rotation of the rotation member can drive all the support columns to rotate synchronously in the same direction.

[0009] In some embodiments, the first end of the threaded rod cooperates with the threaded hole, the yoke includes an outer cylindrical surface, the second end of the threaded rod passes through the outer cylindrical surface, the second end of the threaded rod is provided with gear teeth, the rotating part is sleeved on the outer cylindrical surface, the rotating part is an end face gear, the end face gear is sleeved on the outer cylindrical surface, and the teeth of the end face gear are meshed with the teeth on the threaded rod.

[0010] In some embodiments, a limiting hole is provided on the outer cylindrical surface, and the stator also includes a gear wrench; the end face gear includes a first circle of gear teeth and a second circle of gear teeth opposite to each other, the first circle of gear teeth meshes with the gear teeth on the threaded rod, and when the gear wrench is inserted into the limiting hole, the gear teeth on the gear wrench mesh with the second circle of gear teeth.

[0011] In some embodiments, a plurality of anti-rotation blocks are disposed in the annular groove, and an anti-rotation groove extending along the radial direction of the rotor is disposed on the support column, and the anti-rotation blocks are disposed in the anti-rotation groove.

[0012] In some embodiments, a through hole is provided at the bottom of the annular groove, a limiting ring is provided on the threaded rod, two retaining rings are provided in the through hole, and the two retaining rings are respectively provided on both sides of the limiting ring.

[0013] In some embodiments, in the radial direction of the rotor, from inside to outside, the winding is sequentially provided with a plurality of contacts, and when the pole moves, different contacts can be connected to the circuit.

[0014] The present invention also provides a magnetic suspension bearing, comprising a rotor and the stator.

[0015] The present invention also provides a compressor, characterized in that it comprises the above-mentioned magnetic suspension bearing.

[0016] The present invention designs the magnetic poles of the stator to be able to move in the radial direction, close to or away from the center of the shaft hole. When ensuring that the size of the air gap is within a reasonable range, the diameters of the rotor that can be arranged in the shaft hole are different, thereby improving the applicability of the stator. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. The drawings described below are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0018] Figure 1 is an axial cross-sectional schematic diagram of a stator according to an embodiment of the present invention;

[0019] Figure 2 is an axial cross-sectional schematic diagram of a rotor disposed in the shaft hole of the stator according to an embodiment of the present invention;

[0020] Figure 3 is a partial schematic diagram of a radial cross-sectional view of a stator according to an embodiment of the present invention;

[0021] Figure 4 The embodiment of the present invention Figure 3 Enlarged view of point A in the middle;

[0022] Figure 5 The embodiment of the present invention is Figure 3 A schematic diagram of a case where two anti-rotation blocks are provided on the basis;

[0023] Figure 6 is a schematic diagram of a winding in an embodiment of the present invention when multiple contacts are provided;

[0024] Figure 7 is a schematic diagram of adjusting the stator when the rotor diameter changes in an embodiment of the present invention;

[0025] The accompanying drawings are marked as follows:

[0026] 1. Magnetic yoke; 101. Shaft hole; 102. Annular groove; 103. Threaded hole; 104. Outer cylindrical surface; 105. Limiting hole; 106. Stop block; 107. Retaining ring; 108. Through hole; 2. Pole; 201. Winding; 202. Contact; 203. Selecting end; 3. Support column; 301. Threaded rod; 302. Stop groove; 303. Limiting ring; 4. Air gap; 5. Rotor; 6. Rotating member; 601. First circle gear teeth; 602. Second circle gear teeth; 603. Positioning ring; 7. Gear wrench; DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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 is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0029] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0030] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0031] The present invention provides a stator and a motor, which can solve the technical problem of low universality of the stator of the magnetic suspension bearing in the prior art.

[0032] See also Figure 1-6 As shown, the present invention provides a stator, which is applied to a radial magnetic bearing. The stator is provided with an axial hole 101 for inserting a rotor 5. The stator includes a plurality of poles 2 surrounding the rotor 5. A winding 201 is provided on the pole 2. The first end of the pole 2 faces the rotor 5 and an air gap 4 is formed between the pole 2 and the rotor 5. The plurality of poles 2 can move simultaneously along their own axial direction to change the size of the air gap 4.

[0033] The multiple poles 2 surrounding the rotor 5 in the present application can move away from or close to the rotor 5, which enables the stator to be suitable for rotors 5 of different diameters. When the diameter of the rotor 5 is small, the multiple poles 2 simultaneously move close to the rotor 5, thereby keeping the size of the air gap 4 within a reasonable range; similarly, when the diameter of the rotor 5 is large, the multiple poles 2 simultaneously move away from the rotor 5, thereby keeping the size of the air gap 4 within a reasonable range. In this way, the same stator is suitable for rotors 5 of different diameters, thereby improving the versatility of the stator.

[0034] Preferably, Figure 1-2 As shown, the stator includes a yoke 1 , which is provided with an annular groove 102 opening toward the shaft hole 101 , and the second end of the pole 2 is connected to a support column 3 , which is movably arranged in the annular groove 102 .

[0035] The pole 2 is driven to move by providing the support column 3 , which, on the one hand, facilitates the arrangement of the winding 201 on the pole 2 , and on the other hand, reduces the use of materials for the pole 2 , which is conducive to reducing costs.

[0036] Preferably, Figure 3-4 As shown, a threaded hole 103 is provided at one end of the support column 3 away from the pole 2, and a threaded rod 301 is provided through the bottom surface of the annular groove 102. The threaded rod 301 is adapted to the threaded hole 103, and the rotation of the threaded rod 301 can drive the support column 3 to approach or move away from the axial hole 101.

[0037] A threaded hole 103 is provided on the other end of the support column 3 opposite to the pole 2, and the support column 3 is driven to move by the cooperation between the threaded rod 301 and the threaded hole 103. Specifically, the threaded rod 301 rotates to make the support column 3 approach or move away from the rotor 5. The rotation angle of the threaded rod 301 determines the moving distance of the support column 3. When the threaded rod 301 rotates one circle, the support column only moves one pitch, thus improving the accuracy of adjusting the support column 3. Furthermore, the thread of the threaded hole 103 is fine, which can further improve the accuracy of adjustment. After the threaded rod 301 rotates, the threaded structure has a self-locking function. After the support column 3 is adjusted into place, the support column 3 will no longer move after the threaded rod 301 stops rotating.

[0038] Preferably, Figure 3-4 As shown, the stator further includes a rotation member 6, and the rotation of the rotation member 6 can drive all the support columns 3 to rotate synchronously in the same direction.

[0039] By providing the bearing member 6 to simultaneously drive all the support columns 3 to rotate synchronously in the same direction, the accuracy of adjusting all the stator poles 2 is improved. This is also conducive to making the sizes of multiple air gaps 4 larger or smaller at the same time, which is conducive to maintaining the balance and stability of the force between the stator and the rotor 5.

[0040] Preferably, Figure 3-4 As shown, the first end of the threaded rod 301 cooperates with the threaded hole 103, the yoke 1 includes an outer cylindrical surface 104, the second end of the threaded rod 301 passes through the outer cylindrical surface 104, the second end of the threaded rod 301 is provided with gear teeth, the rotating member 6 is sleeved on the outer cylindrical surface 104, the rotating member 6 is an end face gear, the end face gear is sleeved on the outer cylindrical surface 104, and the gear teeth of the end face gear are meshed with the gear teeth on the threaded rod 301.

[0041] The bearing member 6 is an end face gear, which is sleeved on the outer cylindrical surface 104 for rotation. The outer cylindrical surface 104 forms a radial limit for the end face gear, and the rotation of the end face gear can stably drive all the threaded rods 301 to rotate. The threaded rods 301 are driven to rotate by the gear meshing method. On the one hand, there will be no relative sliding; on the other hand, the linear speed of the end face gear is consistent with the linear speed of the threaded rods 301, which improves the accuracy of the rotation of the threaded rods 301.

[0042] Preferably, Figure 3-4 As shown, a limiting hole 105 is provided on the outer cylindrical surface 104, and the stator also includes a gear wrench 7; the end face gear includes a first circle of gear teeth 601 and a second circle of gear teeth 602 opposite to each other, and the first circle of gear teeth 601 is meshed with the gear teeth on the threaded rod 301, and when the gear wrench 7 is inserted into the limiting hole 105, the gear teeth on the gear wrench 7 are meshed with the second circle of gear teeth 602.

[0043] The first circle of gear teeth 601 and the second circle of gear teeth 602 are respectively arranged on the two end faces of the end gear, and the end gear is driven to rotate by means of the gear wrench 7. Since the gear diameter on the gear wrench 7 is smaller than the diameter of the end gear, that is, the gear wrench 7 rotates multiple circles while the end gear rotates one circle. In this way, the rotation accuracy of the end gear can be improved.

[0044] Furthermore, an annular groove is provided at one end of the inner ring of the end face gear near the limiting hole 105. After the end face gear is sleeved on the outer circumferential surface, a positioning ring 603 is sleeved thereon. Figure 4 As shown, the positioning ring 603 and the plurality of threaded rods 301 limit the end gear along the axial direction of the rotor 5, so that the first ring of gear teeth 601 of the end gear is stably meshed with the gear teeth on the threaded rod 301, and the second ring of gear teeth 602 is stably meshed with the gear teeth on the gear wrench 7. Figure 4 From a viewing angle, the upper end face of the positioning ring 603 has a limiting function for the end face gear, further improving the stability of the rotation of the end face gear.

[0045] Preferably, Figure 3-4As shown, a plurality of anti-rotation blocks 106 are arranged in the annular groove 102 , and an anti-rotation groove 302 extending along the radial direction of the rotor 5 is arranged on the support column 3 , and the anti-rotation blocks 106 are arranged in the anti-rotation groove 302 .

[0046] A stop block 106 is provided in the annular groove 102, and the stop block 106 is fixed in the annular groove 102. The support column 3 is provided with a stop groove 302, and the stop groove 302 extends along the radial direction of the rotor 5. The stop groove 302 cooperates with the stop block 106 to limit the rotation of the support column 3, so that the support column 3 can only move along the radial direction of the rotor 5, thereby improving the accuracy of the movement of the support column 3.

[0047] Further, such as Figure 5 As shown, each support column 3 is provided with two anti-rotation grooves 302 , and the two anti-rotation grooves 302 are radially symmetrically arranged, and an anti-rotation block 106 is arranged in each anti-rotation groove 302 , thereby improving the guiding and anti-rotation effects of the support column 3 .

[0048] Preferably, Figure 3-4 As shown, a through hole 108 is provided at the bottom of the annular groove, a limiting ring 303 is provided on the threaded rod 301 , two retaining rings 107 are provided in the through hole 108 , and the two retaining rings 107 are respectively provided on both sides of the limiting ring 303 .

[0049] By setting two retaining rings 107 in the through hole 108 and setting a limiting ring 303 on the threaded rod 301, in the radial direction of the rotor 5, the two retaining rings 107 clamp the limiting ring 303 on the threaded rod 301 in the middle, and limit the threaded rod 301 in the axial direction (axial direction of the threaded rod 301), so as to prevent the threaded rod 301 from moving away from or close to the rotor 5 when the threaded rod 301 rotates, thereby reducing the effect of the driving support column 3.

[0050] Furthermore, the number of the anti-rotation blocks 106 and the through holes 108 provided in the annular groove 102 is greater than the number of the support columns 3. The support columns 3 can be provided at different positions of the annular groove 102 as required. For example, when the rotor 5 is provided horizontally, more support columns 3 can be provided in the upper and lower directions of the rotor 5 to improve the bearing capacity of the magnetic bearing. The number of the support columns 3 can also be adjusted to adjust the bearing capacity of the rotor 5.

[0051] Preferably, Figure 6 As shown, in the radial direction of the rotor 5, from inside to outside, the winding 201 is sequentially provided with a plurality of contacts 202, and when the pole 2 moves, different contacts 202 can be connected to the circuit.

[0052] Different contacts 202 are connected to the circuit, and the number of coils of the winding 201 entering the circuit is also different. The more coils are connected to the circuit, the greater the inductance is, and the greater the attraction to the rotor 5 is. Specifically, the closer the contact 202 is to the rotor 5, the more coils are connected to the circuit, and the greater the attraction to the rotor 5 is.

[0053] The winding 201 has a fixed end and a movable end. The fixed end is an end close to the yoke 1, and the movable end includes the above-mentioned multiple contacts 202 and a selection end 203 fixed relative to the yoke 1. When the pole 2 is close to the center of the shaft hole 101, since the selection end 203 is stationary relative to the yoke 1, the contact 202 on the pole 2 moves toward the center of the shaft hole 101 at the same time, and the contact 202 connected to the selection end 203 gradually approaches the yoke 1, since the number of coils of the winding 201 is reduced.

[0054] That is, the smaller the diameter of the rotor 5 is, in order to keep the air gap 4 within the design range, the pole 2 moves toward the center of the shaft hole 101, the number of coils connected to the circuit is reduced, and the inductance provided is reduced. Since the diameter of the rotor 5 is reduced, the weight of the rotor 5 (when the rotor 5 is not under load) is also smaller. At this time, the lower inductance can stabilize the resultant force on the rotor 5. That is, when a rotor 5 with a smaller diameter is used, the pole 2 is adjusted to be close to the center of the shaft hole 101. On the one hand, the air gap 4 can be kept within a reasonable range. On the other hand, the number of coils connected to the circuit can be reduced, so that the resultant force on the rotor 5 is stable. When a rotor 5 with a larger diameter is set, the pole 2 is away from the center of the shaft hole 101, the number of coils connected to the circuit increases, and the inductance generated increases. Since the weight of the rotor 5 increases, the resultant force on the rotor 5 can be kept balanced.

[0055] like Figure 6 As shown, the selection end 203 has an arc surface facing the contact 202, and the selection end is fixed on the magnetic yoke. Figure 6 From a perspective, for ease of understanding, the selection end 203 and the contact 202 are separated in the left and right directions, but are actually in contact. When different poles 2 move up and down, the selection end 203 is electrically connected to one contact 202, or the selection end 203 is electrically connected to two adjacent contacts. In this way, when the pole 2 moves up and down, the selection end 203 can always be electrically connected to the contact 202 to avoid the winding 201 from being broken.

[0056] like Figure 7 As shown, the air gap size is adjusted according to the diameter of the rotor to determine whether the rotor is stably suspended. If not, the gear wrench 7 is rotated clockwise or counterclockwise, and the pole 2 is moved closer to or farther from the rotor to adjust the air gap size and the number of coils connected to the circuit. When the rotor can be stably suspended, the gear wrench 7 is kept from rotating and the gear wrench 7 is canceled.

[0057] The present invention also provides a magnetic suspension bearing, comprising a rotor and the stator.

[0058] The present invention also provides a compressor, characterized in that it comprises the above-mentioned magnetic suspension bearing.

[0059] It is easy for those skilled in the art to understand that, without conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions 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 embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention. These improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. A stator, the stator being applied to a radial magnetic bearing, the stator being provided with an axial hole (101) for inserting a rotor (5), the stator comprising a plurality of poles (2) surrounding the rotor (5), characterized in that: A winding (201) is arranged on the pole (2), a first end of the pole (2) faces the rotor (5) and an air gap (4) is formed between the pole and the rotor (5), and a plurality of poles (2) can simultaneously move along their own axial direction to change the size of the air gap (4).

2. The stator according to claim 1, characterized in that: The stator comprises a yoke (1), the yoke (1) being provided with an annular groove (102) opening toward the shaft hole (101), the second end of the pole (2) being connected with a support column (3), the support column (3) being movably arranged in the annular groove (102).

3. The stator according to claim 2, characterized in that: A threaded hole (103) is provided at one end of the support column (3) away from the pole (2), and a threaded rod (301) is provided through the bottom surface of the annular groove (102), the threaded rod (301) is adapted to the threaded hole (103), and the threaded rod (301) can be rotated to drive the support column (3) to approach or move away from the shaft hole (101).

4. The stator according to claim 3, characterized in that: The stator also includes a rotating member (6), and the rotation of the rotating member (6) can drive all the supporting columns (3) to rotate synchronously in the same direction.

5. The stator according to claim 4, characterized in that: The first end of the threaded rod (301) cooperates with the threaded hole (103), the yoke (1) comprises an outer cylindrical surface (104), the second end of the threaded rod (301) passes through the outer cylindrical surface (104), the second end of the threaded rod (301) is provided with gear teeth, the rotating member (6) is sleeved on the outer cylindrical surface (104), the rotating member (6) is an end face gear, the end face gear is sleeved on the outer cylindrical surface (104), and the gear teeth of the end face gear are meshed with the gear teeth on the threaded rod (301).

6. The stator according to claim 5, characterized in that: A limiting hole (105) is provided on the outer cylindrical surface (104); the stator further comprises a gear wrench (7); the end face gear comprises a first circle of gear teeth (601) and a second circle of gear teeth (602) which are opposite to each other; the first circle of gear teeth (601) meshes with the gear teeth on the threaded rod (301); when the gear wrench (7) is inserted into the limiting hole (105), the gear teeth on the gear wrench (7) mesh with the second circle of gear teeth (602).

7. The stator according to claim 2, characterized in that: A plurality of anti-rotation blocks (106) are arranged in the annular groove (102), a anti-rotation groove (302) extending along the radial direction of the rotor (5) is arranged on the support column (3), and the anti-rotation block (106) is arranged in the anti-rotation groove (302).

8. The stator according to claim 3, characterized in that: A through hole (108) is provided at the bottom of the annular groove (102), a limiting ring (303) is provided on the threaded rod (301), two retaining rings (107) are provided in the through hole (108), and the two retaining rings (107) are respectively provided on both sides of the limiting ring (303).

9. The stator according to any one of claims 1 to 8, characterized in that: In the radial direction of the rotor (5), from the inside to the outside, the winding (201) is sequentially provided with a plurality of contacts (202), and when the pole (2) moves, different contacts (202) can be connected to the circuit.

10. A magnetic bearing, characterized in that: It comprises a rotor and a stator as claimed in any one of claims 1 to 9.

11. A compressor, characterized in that: Including the magnetic bearing described in claim 10.

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