Magnetic bearing protection devices, motors, compressors and air conditioners

Abstract

The present application provides a magnetic bearing protection device, a motor, a compressor and an air conditioner. The magnetic bearing protection device includes a rotor, a thrust plate, a front axial core, a rear axial core, a bearing seat, a protective bearing and an axial limiting structure. The thrust plate is installed on the rotor, the front axial core and the rear axial core are located at both ends of the thrust plate, the bearing seat is fixed relative to the rear axial core, and both ends of the inner ring of the bearing seat are provided with axial limiting structures. The axial limiting structures cooperate with the internal threads of the bearing seat and lock the axial position of the outer ring of the protective bearing. A stop step and a rear stop shoulder are provided on the rotor. The stop step and the rear stop shoulder form a limiting groove, and the inner ring of the protective bearing is located in the limiting groove. According to the magnetic bearing protection device of the present application, when the rotor is axially unstable, it can effectively avoid the collision between the thrust plate and the magnetic bearing, thereby improving the operating reliability of the magnetic bearing.

Description

Technical Field

[0001] The present application relates to the technical field of bearings, and in particular to a magnetic bearing protection device, a motor, a compressor and an air conditioner. Background Art

[0002] Related technologies disclose a method for adjusting the assembly gap between a magnetic bearing, an auxiliary bearing and a rotor, which applies a load to a compressible and deformable spring laminate through a clamping block to adjust the axial position of the protective bearing in the bearing seat, thereby changing the projection position on the rotor. However, the spring laminate has a small stiffness and poor impact resistance. When the rotor becomes axially unstable and collides, there is a risk of failure of the spring laminate or large deformation, resulting in a collision between the thrust plate and the magnetic bearing. Summary of the invention

[0003] Therefore, the technical problem to be solved by the present application is to provide a magnetic bearing protection device, a motor, a compressor and an air conditioner, which can effectively prevent the thrust plate from colliding with the magnetic bearing when the rotor is axially unstable, thereby improving the operating reliability of the magnetic bearing.

[0004] In order to solve the above problems, the present application provides a magnetic levitation bearing protection device, including a rotor, a thrust plate, a front axial iron core, a rear axial iron core, a bearing seat, a protective bearing and an axial limiting structure. The thrust plate is installed on the rotor, and the front axial iron core and the rear axial iron core are located at both ends of the thrust plate. The bearing seat is fixed relative to the rear axial iron core. Both ends of the inner ring of the bearing seat are provided with axial limiting structures. The axial limiting structures cooperate with the internal thread of the bearing seat and lock the axial position of the outer ring of the protective bearing. A stop step and a rear stop shoulder are provided on the rotor. The stop step and the rear stop shoulder form a limiting groove. The inner ring of the protective bearing is located in the limiting groove. The gap between the inner ring and the stop step is d1, the gap between the inner ring and the rear stop shoulder is d2, the gap between the thrust plate and the front axial iron core is b1, and the gap between the thrust plate and the rear axial iron core is b2, wherein b1>d2, b2>d1.

[0005] Preferably, the axial limiting structure includes a screw plug and an outer ring shoulder. The bearing seat limits the axial position of the outer ring of the protective bearing through the outer ring shoulders at both ends. The screw plug cooperates with the internal thread of the bearing seat to lock the axial position of the outer ring shoulder.

[0006] Preferably, a radial stator core is further sleeved outside the rotor, a radial gap between the radial stator core and the rotor is a, a radial gap between the protective bearing and the rotor is c, and a>c.

[0007] Preferably, the inner peripheral wall of the bearing seat further includes a radial positioning section, the radial positioning section is located between the two outer ring shoulders, and the protective bearing is arranged in the radial positioning section.

[0008] Preferably, the inner circumferential wall of the bearing seat also includes a recessed groove section, a step is formed between the recessed groove section and the radial positioning section, the internal thread is located on the side wall of the recessed groove section, the recessed groove section includes a threaded section and a smooth section, the screw plug is threadably matched with the threaded section, and the outer ring shoulder is slidably matched with the smooth section.

[0009] Preferably, a torque locking groove is provided at one end of the screw plug away from the thrust plate.

[0010] Preferably, the torque locking groove penetrates the screw plug axially.

[0011] Preferably, the torque locking groove is located on the inner peripheral wall of the screw plug.

[0012] Preferably, a portion of the rotor located axially outside the protective bearing is provided with a positioning step, and the rear shoulder is axially limited on the positioning step.

[0013] Preferably, the rotor is provided with an external thread, the rear shoulder has an internal thread, and the rear shoulder and the rotor are thread-matched.

[0014] Preferably, the rotor is provided with an external thread, and a locking nut is provided on the axial outer side of the rear shoulder. The locking nut cooperates with the rotor thread and is locked on the axial outer side of the rear shoulder.

[0015] Preferably, the screw plug and the bearing seat are matched with a fine thread.

[0016] Preferably, the protective bearing is a deep groove ball bearing or an angular contact ball bearing.

[0017] Preferably, the protective bearing is a ceramic ball bearing.

[0018] According to another aspect of the present application, a motor is provided, comprising a magnetic bearing protection device, wherein the magnetic bearing protection device is the above-mentioned magnetic bearing protection device.

[0019] According to another aspect of the present application, a compressor is provided, comprising a magnetic bearing protection device, wherein the magnetic bearing protection device is the above-mentioned magnetic bearing protection device.

[0020] According to another aspect of the present application, an air conditioner is provided, comprising a magnetic bearing protection device, wherein the magnetic bearing protection device is the above-mentioned magnetic bearing protection device.

[0021] The magnetic bearing protection device provided by the present application includes a rotor, a thrust plate, a front axial iron core, a rear axial iron core, a bearing seat, a protective bearing and an axial limiting structure. The thrust plate is installed on the rotor, and the front axial iron core and the rear axial iron core are located at both ends of the thrust plate. The bearing seat is fixed relative to the rear axial iron core. Both ends of the inner ring of the bearing seat are provided with axial limiting structures. The axial limiting structures cooperate with the internal thread of the bearing seat and lock the axial position of the outer ring of the protective bearing. A stop step and a rear stop shoulder are provided on the rotor. The stop step and the rear stop shoulder form a limiting groove. The inner ring of the protective bearing is located in the limiting groove. The gap between the inner ring and the stop step is d1, the gap between the inner ring and the rear stop shoulder is d2, the gap between the thrust plate and the front axial iron core is b1, and the gap between the thrust plate and the rear axial iron core is b2, wherein b1>d2, b2>d1. The magnetic bearing protection device installs the protection bearing in the bearing seat, and adjusts the axial installation position of the protection bearing by means of a spiral pair formed between the axial limiting structure arranged at both ends of the bearing and the bearing seat, so that the axial position of the protection bearing can be easily adjusted, making the magnetic bearing protection device more versatile and simplifying the assembly process. At the same time, the axial adjustment formed by the spiral pair can be used to ensure the impact resistance of the protection bearing, and can effectively avoid the collision between the thrust plate and the magnetic bearing when the rotor is axially unstable, thereby improving the operating reliability of the magnetic bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic structural diagram of a magnetic bearing protection device according to an embodiment of the present application;

[0023] Figure 2 A schematic diagram of the structure of a screw plug of a magnetic bearing protection device according to an embodiment of the present application.

[0024] The reference numerals are:

[0025] 1. Rotor; 2. Radial stator core; 3. Front axial core; 4. Rear axial core; 5. Bearing seat; 6. Protective bearing; 7. Screw plug; 71. Torque locking groove; 8. Outer ring shoulder; 9. Locking nut; 10. Rear shoulder; 11. Thrust plate; 12. Radial positioning section; 13. Stop step; 14. Positioning step. DETAILED DESCRIPTION

[0026] See also Figure 1 to Figure 2As shown, according to an embodiment of the present application, the magnetic bearing protection device includes a rotor 1, a thrust plate 11, a front axial core 3, a rear axial core 4, a bearing seat 5, a protective bearing 6 and an axial limiting structure. The thrust plate 11 is installed on the rotor 1, the front axial core 3 and the rear axial core 4 are located at both ends of the thrust plate 11, the bearing seat 5 is fixed relative to the rear axial core 4, and both ends of the inner ring of the bearing seat 5 are provided with axial limiting structures, and the axial limiting structure cooperates with the internal thread of the bearing seat 5. And lock the axial position of the outer ring of the protective bearing 6, a stop step 13 and a rear shoulder 10 are provided on the rotor 1, the stop step 13 and the rear shoulder 10 form a limiting groove, the inner ring of the protective bearing 6 is located in the limiting groove, the gap between the inner ring and the stop step 13 is d1, the gap between the inner ring and the rear shoulder 10 is d2, the gap between the thrust plate 11 and the front axial iron core 3 is b1, the gap between the thrust plate 11 and the rear axial iron core 4 is b2, wherein b1>d2, b2>d1.

[0027] The magnetic bearing protection device installs the protection bearing 6 in the bearing seat 5, and adjusts the axial installation position of the protection bearing 6 by means of a spiral pair formed between the axial limiting structure arranged at both ends of the bearing and the bearing seat 5, so that the axial position of the protection bearing 6 can be easily adjusted, making the magnetic bearing protection device more versatile and simplifying the assembly process. At the same time, the axial adjustment formed by the spiral pair can be used to ensure the impact resistance of the protection bearing, and can effectively avoid the collision between the thrust plate and the magnetic bearing when the rotor is axially unstable, thereby improving the operating reliability of the magnetic bearing.

[0028] In this embodiment, since there is a threaded fitting relationship between the axial limiting structure and the bearing seat 5, the axial position of the axial limiting structure can be adjusted by using the threaded fitting. Therefore, different axial clearances between the protective bearing and the stop step 13 of the rotor 1 and the rear shoulder 10 can be adjusted according to different magnetic bearings and rotors, so that the threaded fitting structure between the axial limiting structure and the bearing seat 5 can be suitable for different types of protective bearing settings, with better adaptability and simpler assembly requirements.

[0029] In this embodiment, when the rotor 1 loses stability, if the rotor 1 moves forward, since the axial gap between the thrust plate 11 and the front axial core 3 is b1, and the axial gap between the inner ring and the rear shoulder 10 is d2, b1>d2, the rotor 1 will drive the rear shoulder 10 to move forward, and the rear shoulder 10 will first contact the protective bearing 6, so it can prevent the thrust plate 11 from hitting the front axial core 3, forming effective axial protection for the front axial core 3.

[0030] Similarly, if the rotor 1 moves backward, since the axial gap between the thrust plate 11 and the rear axial core 4 is b2, and the axial gap between the inner ring and the stop step 13 is d1, b2>d1, the rotor 1 will drive the stop step 13 to move backward, and the stop step 13 will first contact the protective bearing 6, thereby preventing the thrust plate 11 from hitting the rear axial core 4, thereby forming effective axial protection for the rear axial core 4.

[0031] In one embodiment, (b1+b2)>(d1+d2), b1=b2, d1=d2, which can ensure the centering of the protective bearing 6 and improve the protective performance of the protective bearing 6 on the magnetic bearing.

[0032] In one embodiment, a radial stator core 2 is further sleeved outside the rotor 1, a radial gap between the radial stator core 2 and the rotor 1 is a, a radial gap between the protective bearing 6 and the rotor 1 is c, and a>c.

[0033] In this embodiment, since a>c, when the rotor 1 loses stability and moves radially, the rotor 1 will first contact the inner ring of the protective bearing 6 and be stopped by the inner ring of the protective bearing 6, so it will not come into contact with the radial stator core 2, which can effectively protect the radial stator core 2 and prevent the rotor 1 from colliding with the radial stator core 2 and damaging the radial stator core 2.

[0034] The protective bearing 6 of this embodiment can provide both axial protection and radial protection for the magnetic bearing, thus integrating the radial protection and axial protection of the magnetic bearing into one, simplifying the structure of the magnetic bearing protection system, reducing accessories, and effectively reducing costs.

[0035] The axial limiting structure includes a screw plug 7 and an outer ring shoulder 8. The outer ring shoulders 8 at both ends of the bearing seat 5 limit the axial position of the outer ring of the protective bearing 6. The screw plug 7 cooperates with the internal thread of the bearing seat 5 to lock the axial position of the outer ring shoulder 8. In this embodiment, the axial limiting structure is set as a split structure, and the axial matching accuracy between the outer ring shoulder 8 and the protective bearing 6 can be achieved through the outer ring shoulder 8, and the axial position of the protective bearing 6 can be locked by the screw plug 7. Therefore, the processing accuracy requirements for the screw plug 7 can be greatly reduced, and the structural complexity of the outer ring shoulder 8 is also reduced, and the axial limiting structure is divided according to the function. Therefore, while reducing the overall processing accuracy requirements of the axial limiting structure, the processing difficulty of the axial limiting structure can be reduced, the processing efficiency can be improved, and the axial positioning accuracy of the protective bearing 6 can be more easily guaranteed.

[0036] In one embodiment, the axial limiting structure can also be set as an integral structure, that is, the axial positioning and locking functions of the axial limiting structure are integrated. In this embodiment, the screw plug 7 can be omitted, and an external thread is set on the outer periphery of the outer ring shoulder 8. The external thread of the outer ring shoulder 8 cooperates with the internal thread of the bearing seat 5 to achieve axial position locking, and the end face of the outer ring shoulder 8 cooperates with the outer ring of the protective bearing 6 to achieve axial positioning of the outer ring of the protective bearing 6. This structure is more compact, but in order to ensure the axial matching accuracy with the protective bearing 6, it is necessary to improve the matching accuracy of the external thread and the internal thread of the bearing seat 5.

[0037] In one embodiment, the inner peripheral wall of the bearing seat 5 further includes a radial positioning section 12, the radial positioning section 12 is located between the two outer ring shoulders 8, and the protective bearing 6 is arranged in the radial positioning section 12. In this embodiment, the protective bearing 6 cooperates with the radial positioning section 12, and the radial positioning section 12 ensures the radial matching accuracy between the protective bearing 6 and the rotor 1. In this embodiment, there is a clearance fit between the radial positioning section 12 and the outer ring of the protective bearing 6, preferably a small clearance fit, which can reduce the difficulty of installing the protective bearing 6 and ensure the radial matching accuracy between the protective bearing 6 and the rotor 1.

[0038] In one embodiment, the inner peripheral wall of the bearing seat 5 further includes a recessed groove section, a step is formed between the recessed groove section and the radial positioning section 12, the internal thread is located on the side wall of the recessed groove section, the recessed groove section includes a threaded section and a smooth section, the screw plug 7 is threadedly matched with the threaded section, and the outer ring shoulder 8 is slidably matched with the smooth section. In this embodiment, by setting the recessed groove section, the bearing seat 5 can be designed in sections, so that the radial positioning section 12 and the threaded connection section including the internal thread are at different radial heights, and the processing accuracy of the radial positioning section can be guaranteed without affecting the setting of the internal thread, and the radial positioning section can be conveniently matched with the protective bearing 6 to radially position the protective bearing 6. Similarly, by setting the threaded section and the smooth section in the recessed groove section, not only can the installation and positioning of the screw plug 7 be conveniently realized through the threaded section, but also the axial positioning accuracy of the outer ring shoulder 8 can be effectively guaranteed through the matching of the smooth section and the outer ring shoulder 8.

[0039] In one embodiment, a torque locking groove 71 is provided at one end of the screw plug 7 away from the thrust plate 11. In this embodiment, the torque locking groove 71 can be operated by torque, so it is convenient to apply torque to the screw plug 7 during the process of adjusting the axial position of the protective bearing 6, reducing the difficulty of adjustment. The number of the torque locking grooves 71 is, for example, two, and they are arranged symmetrically along the end surface center of the screw plug 7.

[0040] In one embodiment, the torque locking groove 71 penetrates the screw plug 7 axially, so that the operating end of the torque locking groove 71 is not restricted, making it more convenient to operate the screw plug 7.

[0041] In one embodiment, the torque locking groove 71 is located on the inner circumferential wall of the screw plug 7 , which can facilitate the operation of the screw plug 7 while reducing the influence of the setting of the torque locking groove 71 on the structural strength of the screw plug 7 .

[0042] The portion of the rotor 1 located axially outside the protective bearing 6 is provided with a positioning step 14, and the rear shoulder 10 is axially limited on the positioning step 14. In this embodiment, through the cooperation of the positioning step 14 and the rear shoulder 10, the axial position of the rear shoulder 10 can be accurately positioned, thereby ensuring the axial limiting accuracy of the rear shoulder 10 to the protective bearing.

[0043] The rotor 1 is provided with an external thread, and the rear shoulder 10 has an internal thread, and the rear shoulder 10 and the rotor 1 are threadedly matched. In this embodiment, the rear shoulder 10 not only realizes the axial limit of the protective bearing 6, but also realizes its own axial positioning by using the thread structure. In this embodiment, the axial limit of the rotor 1 for the protective bearing 6 and the rear shoulder 10 is realized by providing a step shaft to form a step.

[0044] The rotor 1 is provided with an external thread, and a locking nut 9 is provided on the axial outer side of the rear shoulder 10. The locking nut 9 is matched with the thread of the rotor 1, and the locking nut 9 is locked on the axial outer side of the rear shoulder 10. In this embodiment, the axial limit accuracy of the rear shoulder 10 for protecting the bearing 6 is achieved by the processing accuracy of the rear shoulder 10 itself and the matching accuracy of the rotor 1. The processing accuracy of the locking nut 9 does not need to be considered, and it only needs to be able to lock the axial position of the rear shoulder 10. Therefore, the processing accuracy requirement is reduced, the processing cost is lower, and the axial limit accuracy of the protective bearing 6 is also easier to ensure.

[0045] The screw plug 7 and the bearing seat 5 are matched with fine pitch threads. In this embodiment, the thread type of the screw pair is preferably a fine pitch metric triangular thread, which has good self-locking properties and can effectively improve the self-locking performance between the screw plug 7 and the bearing seat 5.

[0046] In one embodiment, the protective bearing 6 is a deep groove ball bearing or an angular contact ball bearing, and may be a steel ball bearing or a ceramic ball bearing.

[0047] As a preferred embodiment, the protective bearing 6 is a ceramic ball bearing.

[0048] During the assembly process of the magnetic suspension bearing protection device, the screw plug 7 and the outer ring shoulder 8 are not locked first, so that there is a certain axial clearance between the outer ring shoulder 8 and the protective bearing 6, and the protective bearing 6 can slide freely between the outer ring shoulders 8 at both ends. The rotor 1 is sucked to the rear end, at which time the thrust plate 11 fits with the rear axial core 4, and the screw plug 7 is screwed forward so that the protective bearing 6 fits with the stop step 13, and then the rear end screw plug 7 is screwed forward by (b1+b2-d1-d2) / 2, that is, the axial clearance is adjusted to the right position. When the rotor 1 is suspended, the thrust plate 11 is located between the front axial core 3 and the rear axial core 4 under the action of the axial magnetic suspension force, and the protective bearing 6 is located between the stop step 13 and the rear shoulder 10. The bearing seat 5 is disassembled, and the screw plugs 7 on both sides of the protective bearing 6 are tightened alternately with increasing torque, and then the bearing seat 5 is installed on the rear axial core 4 to complete the assembly of the magnetic suspension bearing protection device.

[0049] According to an embodiment of the present application, the motor includes a magnetic bearing protection device, which is the magnetic bearing protection device mentioned above.

[0050] According to an embodiment of the present application, the compressor includes a magnetic bearing protection device, which is the above-mentioned magnetic bearing protection device.

[0051] According to an embodiment of the present application, the air conditioner includes a magnetic bearing protection device, which is the above-mentioned magnetic bearing protection device.

[0052] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0053] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. 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 application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A magnetic bearing protection device, characterized in that: The invention comprises a rotor (1), a thrust plate (11), a front axial core (3), a rear axial core (4), a bearing seat (5), a protective bearing (6) and an axial limiting structure, wherein the thrust plate (11) is mounted on the rotor (1), the front axial core (3) and the rear axial core (4) are located at two ends of the thrust plate (11), the bearing seat (5) is fixedly arranged relative to the rear axial core (4), and the axial limiting structure is arranged at both ends of the inner ring of the bearing seat (5), the axial limiting structure cooperates with the internal thread of the bearing seat (5), and locks the protective bearing (6) ), the rotor (1) is provided with a stop step (13) and a rear shoulder (10), the stop step (13) and the rear shoulder (10) form a limit groove, the inner ring of the protective bearing (6) is located in the limit groove, the gap between the inner ring and the stop step (13) is d1, the gap between the inner ring and the rear shoulder (10) is d2, the gap between the thrust plate (11) and the front axial core (3) is b1, and the gap between the thrust plate (11) and the rear axial core (4) is b2, wherein b1>d2, b2>d1.

2. The magnetic bearing protection device according to claim 1, characterized in that: The axial limiting structure includes a screw plug (7) and an outer ring shoulder (8); the bearing seat (5) limits the axial position of the outer ring of the protective bearing (6) through the outer ring shoulders (8) at both ends; the screw plug (7) cooperates with the internal thread of the bearing seat (5) to lock the axial position of the outer ring shoulder (8).

3. The magnetic bearing protection device according to claim 1, characterized in that: A radial stator core (2) is also sleeved outside the rotor (1), a radial gap between the radial stator core (2) and the rotor (1) is a, and a radial gap between the protective bearing (6) and the rotor (1) is c, where a>c.

4. The magnetic bearing protection device according to claim 2, characterized in that: The inner peripheral wall of the bearing seat (5) further comprises a radial positioning section (12), wherein the radial positioning section (12) is located between the two outer ring shoulders (8), and the protective bearing (6) is arranged in the radial positioning section (12).

5. The magnetic bearing protection device according to claim 4, characterized in that: The inner peripheral wall of the bearing seat (5) also includes a recessed groove section, a step is formed between the recessed groove section and the radial positioning section (12), the internal thread is located on the side wall of the recessed groove section, the recessed groove section includes a threaded section and a smooth section, the screw plug (7) is threadedly matched with the threaded section, and the outer ring shoulder (8) is slidingly matched with the smooth section.

6. The magnetic bearing protection device according to claim 2, characterized in that: A torque locking groove (71) is provided at one end of the screw plug (7) away from the thrust plate (11).

7. The magnetic bearing protection device according to claim 6, characterized in that: The torque locking groove (71) penetrates the screw plug (7) in the axial direction.

8. The magnetic bearing protection device according to claim 7, characterized in that: The torque locking groove (71) is located on the inner peripheral wall of the screw plug (7).

9. The magnetic bearing protection device according to claim 1, characterized in that: A portion of the rotor (1) located axially outside the protective bearing (6) is provided with a positioning step (14), and the rear shoulder (10) is axially limited on the positioning step (14).

10. The magnetic bearing protection device according to claim 9, characterized in that: The rotor (1) is provided with an external thread, the rear shoulder (10) has an internal thread, and the rear shoulder (10) and the rotor (1) are thread-matched.

11. The magnetic bearing protection device according to claim 10, characterized in that: The rotor (1) is provided with an external thread, and a locking nut (9) is provided on the axial outer side of the rear shoulder (10). The locking nut (9) is threadably matched with the rotor (1), and the locking nut (9) is locked on the axial outer side of the rear shoulder (10).

12. The magnetic bearing protection device according to claim 2, characterized in that: The screw plug (7) and the bearing seat (5) are matched with each other in a fine pitch thread.

13. The magnetic bearing protection device according to claim 1, characterized in that: The protective bearing (6) is a deep groove ball bearing or an angular contact ball bearing.

14. The magnetic bearing protection device according to claim 13, characterized in that: The protective bearing (6) is an angular contact ceramic ball bearing.

15. A motor, comprising a magnetic bearing protection device, characterized in that: The magnetic bearing protection device is the magnetic bearing protection device according to any one of claims 1 to 14.

16. A compressor, comprising a magnetic bearing protection device, characterized in that: The magnetic bearing protection device is the magnetic bearing protection device according to any one of claims 1 to 14.

17. An air conditioner, comprising a magnetic bearing protection device, characterized in that: The magnetic bearing protection device is the magnetic bearing protection device according to any one of claims 1 to 14.

Images