Rotating shaft assembly, rotating shaft axial magnetic suspension positioning structure, compressor, air conditioner

Abstract

The present invention provides a rotating shaft assembly, a rotating shaft axial magnetic suspension positioning structure, a compressor, and an air conditioner, wherein the rotating shaft assembly includes a rotating shaft, the rotating shaft includes a first shaft section, a positioning sleeve is mounted on the first shaft section, the positioning sleeve has a radial positioning barrel section that is interference-fitted with the first shaft section, and a thrust plate is interference-fitted on the outer periphery of the radial positioning barrel section. According to the present invention, the radial or axial jumping phenomenon caused by the tooth gap existing in the threaded connection in the prior art can be avoided, so that the axial radial positioning of the thrust plate is more reliable, and when the thrust plate is subjected to a large load, it will not deform like the thread teeth in the prior art, thereby ensuring that the thrust plate does not have radial fluctuations; the positioning assembly structure is simpler, and the assembly or maintenance efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of compressor manufacturing, and in particular relates to a rotating shaft assembly, a rotating shaft axial magnetic suspension positioning structure, a compressor, and an air conditioner. Background Art

[0002] Magnetic bearings have a series of excellent qualities such as no contact, no wear, high speed, high precision, no need for lubrication and sealing, etc. They are high-tech products integrating electromagnetism, electronic technology, control engineering, signal processing and mechanics.

[0003] Magnetic bearings are divided into three types: active, passive, and hybrid. Active magnetic bearings have high stiffness and can be precisely controlled, but the volume and power consumption required to produce unit load-bearing capacity are large; passive magnetic bearings use the attraction or repulsion between magnetic materials to achieve rotor suspension, and have relatively low stiffness and damping; hybrid magnetic bearings use permanent magnets to provide a bias magnetic field to replace the static bias magnetic field generated by the electromagnet in active magnetic bearings, reduce the ampere-turns of the control winding, reduce the volume of the bearing, and improve the bearing capacity; hybrid magnetic bearings have irreplaceable advantages in areas with strict requirements on volume and power consumption, and magnetic bearings are mainly used in high-speed and ultra-high-speed applications. Therefore, the integration and miniaturization of magnetic suspension systems and improving the stability and reliability of control systems will be key research directions.

[0004] The magnetic suspension axial bearing realizes the axial suspension control of the rotating shaft, and the thrust plate is the core moving component. The original thrust plate installation method is as follows Figure 4 As shown, the support ring 20 is connected and fixed to the rotating shaft 10 by means of threads, and the support ring 20 is made of non-magnetic material; the thrust plate 30 is connected and fixed to the support ring 20 by means of threads, and the locking nut 40 is connected and fixed to the rotating shaft 10 by means of threads, thereby realizing axial fixation of the thrust plate 30 and the support ring 20, and the axial bearing assembly 50 performs axial suspension control on the thrust plate 40, thereby realizing axial suspension of the rotating shaft 10. The thrust plate 30 is the core load-bearing component for the axial suspension control of the rotating shaft 10, and high-precision radial and axial positioning are required. The existing technology has the following technical status: ① The thrust plate is positioned axially through a support ring and a locking nut. The thrust plate, the locking nut and the rotating shaft are threadedly connected. When the thrust plate is subjected to a large axial load, there is a gap between the threaded parts, and the axial movement of the thrust plate is large, and the axial suspension accuracy is low; ② The thrust plate is radially fixed and supported by a threaded step and a support ring. When there is a gap in the threaded connection and the threaded step is subjected to a large radial load, the thread teeth are easily deformed. When the rotating shaft runs at high speed, the radial fluctuation of the thrust plate is large, and the reliability of the magnetic suspension system is low. Summary of the invention

[0005] Therefore, the present invention provides a shaft assembly, a shaft axial magnetic suspension positioning structure, a compressor, and an air conditioner, which can overcome the shortcomings of the thrust plate installation positioning structure in the related art that is realized by threads and has large axial and radial movements.

[0006] In order to solve the above problems, the present invention provides a rotating shaft assembly, including a rotating shaft, wherein the rotating shaft includes a first shaft section, a positioning sleeve is mounted on the first shaft section, the positioning sleeve has a radial positioning barrel section that is interference fit with the first shaft section, and a thrust plate is interference fit on the outer periphery of the radial positioning barrel section.

[0007] Preferably, the rotating shaft also includes a second shaft segment, the first shaft segment and the second shaft segment are adjacently arranged along the axial direction of the rotating shaft, the diameter of the first shaft segment is smaller than the diameter of the second shaft segment to form a shaft shoulder at the junction of the two, the positioning sleeve also has an axial positioning barrel segment abutting the shaft shoulder, and the thrust plate abuts the axial positioning barrel segment on the side facing the shaft shoulder.

[0008] Preferably, the outer diameter of the radial positioning barrel section is smaller than the outer diameter of the axial positioning barrel section.

[0009] Preferably, the radial positioning barrel section and the axial positioning barrel section are independent barrels.

[0010] Preferably, the positioning sleeve is made of non-magnetic material or weakly magnetic material.

[0011] Preferably, the thermal expansion coefficient of the material of the thrust disk is greater than the thermal expansion coefficient of the material of the radial positioning barrel section.

[0012] The present invention also provides an axial magnetic suspension positioning structure of a rotating shaft, comprising a rotating shaft assembly and an axial magnetic bearing assembly, wherein the axial magnetic bearing assembly can exert an axial force on the rotating shaft assembly, and the rotating shaft assembly is the above-mentioned rotating shaft assembly.

[0013] Preferably, the axial magnetic bearing assembly comprises a front bearing assembly and a rear bearing assembly, the front bearing assembly and the rear bearing assembly are arranged opposite to each other, and the front bearing assembly and the rear bearing assembly are respectively located at opposite ends of the thrust plate.

[0014] The present invention also provides a compressor, comprising the above-mentioned rotating shaft axial magnetic suspension positioning structure.

[0015] The present invention also provides an air conditioner, comprising the above-mentioned compressor.

[0016] The present invention provides a rotating shaft assembly, a rotating shaft axial magnetic suspension positioning structure, a compressor, and an air conditioner. The thrust plate, the radial positioning cylinder section, and the rotating shaft are radially integrated by interference fit. On the one hand, the radial or axial jump phenomenon caused by the tooth gap existing in the connection using threaded parts in the prior art can be avoided, so that the axial radial positioning of the thrust plate is more reliable, and when it is used in conjunction with the magnetic bearing, the suspension accuracy of the magnetic bearing can be improved; on the other hand, the inner ring wall surface of the thrust plate of the present application is a smooth radial support surface instead of the thread teeth in the prior art. When the thrust plate is subjected to a large load, it will not deform like the thread teeth in the prior art, thereby ensuring that the thrust plate does not undergo radial fluctuations; on the other hand, the positioning assembly structure of the thrust plate in the present application is simpler, thereby improving the assembly or maintenance efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the internal structure of the shaft axial magnetic suspension positioning structure according to an embodiment of the present invention;

[0018] Figure 2 for Figure 1 A schematic diagram of the three-dimensional structure of the rotating shaft axial magnetic suspension positioning structure;

[0019] Figure 3 for Figure 1 A schematic diagram of the disassembled structure of the rotating shaft axial magnetic suspension positioning structure;

[0020] Figure 4 It is a schematic diagram of the internal structure of the shaft axial magnetic suspension positioning structure in the prior art.

[0021] The reference numerals are:

[0022] 1. Rotating shaft; 11. First shaft section; 12. Second shaft section; 2. Positioning sleeve; 21. Radial positioning cylinder section; 22. Axial positioning cylinder section; 3. Thrust plate; 200. Axial magnetic bearing assembly; 201. Front bearing assembly; 202. Rear bearing assembly; 10. Rotating shaft; 20. Support ring; 30. Thrust plate; 40. Locking nut; 50. Axial bearing assembly. DETAILED DESCRIPTION

[0023] See also Figures 1 to 3As shown, according to an embodiment of the present invention, a shaft assembly is provided, including a shaft 1, wherein the shaft 1 includes a first shaft segment 11, a positioning sleeve 2 is sleeved on the first shaft segment 11, the positioning sleeve 2 has a radial positioning barrel segment 21 which is interference fit with the first shaft segment 11, and a thrust plate 3 is interference fit on the outer periphery of the radial positioning barrel segment 21. In this technical solution, the thrust plate 3, the radial positioning cylinder section 21 and the rotating shaft 1 are radially integrated by interference fit. On the one hand, it can avoid the radial or axial jump phenomenon caused by the tooth gap existing in the connection with threaded parts in the prior art, so that the axial radial positioning of the thrust plate 3 is more reliable, and when it is used in conjunction with the magnetic bearing, it can improve the suspension accuracy of the magnetic bearing; on the other hand, the inner ring wall surface of the thrust plate 3 of the present application is a smooth radial support surface instead of the thread teeth in the prior art. When the thrust plate 3 is subjected to a large load, it will not deform like the thread teeth in the prior art, thereby ensuring that the thrust plate 3 does not undergo radial fluctuations; on the other hand, the positioning assembly structure of the thrust plate 3 in the present application is simpler, thereby improving the assembly or maintenance efficiency.

[0024] In some embodiments, the rotating shaft 1 further includes a second shaft segment 12, the first shaft segment 11 and the second shaft segment 12 are adjacently arranged along the axial direction of the rotating shaft 1, the diameter of the first shaft segment 11 is smaller than the diameter of the second shaft segment 12 to form a shaft shoulder at the junction of the two, the positioning sleeve 2 also includes an axial positioning barrel segment 22 abutting against the shaft shoulder, and the thrust plate 3 abuts against the axial positioning barrel segment 22 on the side facing the shaft shoulder. In this technical solution, the positioning sleeve 2 is axially positioned by the axial positioning barrel segment 22 of the positioning sleeve 2 and the shaft shoulder, thereby improving the stability of the axial position of the thrust plate 3.

[0025] In some embodiments, the outer diameter of the radial positioning barrel segment 21 is smaller than the outer diameter of the axial positioning barrel segment 22 , so that one side of the thrust plate 3 can fit with one side of the axial positioning barrel segment 22 , making axial positioning more convenient.

[0026] In some embodiments, the radial positioning barrel segment 21 and the axial positioning barrel segment 22 are respectively independent barrels, that is, the positioning sleeve 2 is formed by assembling the radial positioning barrel segment 21 and the axial positioning barrel segment 22 which are independent of each other. In this way, on the one hand, the radial positioning barrel segment 21 and the axial positioning barrel segment 22 can be more flexible in the selection of materials. On the other hand, designing the two as independent components can effectively avoid the difference in wall thickness when the two parts are heated during interference fit as a whole, which leads to the difference in expansion size of the two parts, increasing the difficulty of assembly.

[0027] In some embodiments, when the rotating shaft assembly is applied to a magnetic levitation system, the thrust plate 3 in the rotating shaft assembly will be used in combination with the corresponding axial magnetic levitation bearing to limit the axial displacement of the rotating shaft 1, and at the same time, the rotating shaft assembly will also be supported by the corresponding radial magnetic levitation bearing. Generally speaking, when the axial spacing between the radial magnetic levitation bearing and the axial magnetic levitation bearing is large, the magnetic leakage at the rotating shaft 1 will not be too serious. When the axial spacing between the two is small, in order to prevent the magnetic leakage of the axial magnetic levitation bearing at the rotating shaft 1, preferably, the material of the positioning sleeve 2 is aluminum, copper, or other non-magnetic materials or weakly magnetic materials.

[0028] In some embodiments, the thermal expansion coefficient of the material of the thrust disk 3 is greater than the thermal expansion coefficient of the material of the radial positioning barrel segment 21, so that when the thrust disk 3 needs to be disassembled for maintenance and the thrust disk 3 needs to be heated, the thrust disk 3 can be disassembled alone and the radial positioning barrel segment 21 can be retained on the first shaft segment 11, thereby improving the efficiency of maintenance work.

[0029] According to an embodiment of the present invention, there is also provided an axial magnetic suspension positioning structure of a rotating shaft, comprising a rotating shaft assembly (not labeled in the figure) and an axial magnetic bearing assembly 200, wherein the axial magnetic bearing assembly 200 can apply an axial force to the rotating shaft assembly, and the rotating shaft assembly is the above-mentioned rotating shaft assembly. Specifically, the axial magnetic bearing assembly 200 comprises a front bearing assembly 201 and a rear bearing assembly 202, wherein the front bearing assembly 201 and the rear bearing assembly 202 are arranged opposite to each other, and the front bearing assembly 201 and the rear bearing assembly 202 are respectively located at opposite ends of the thrust plate 3. The front bearing assembly 201 and the rear bearing assembly 202 respectively have corresponding stator cores, control windings (providing a control magnetic circuit), and magnetic rings (providing a bias magnetic circuit) and magnetic conductive rings between the two, and as the technology known in the industry, the present invention will not elaborate on them.

[0030] According to an embodiment of the present invention, there is also provided a compressor, comprising the above-mentioned rotating shaft axial magnetic suspension positioning structure.

[0031] According to an embodiment of the present invention, an air conditioner is also provided, comprising the above-mentioned compressor. It is understandable that the compressor has a corresponding housing, and the housing is configured with a bearing chamber for fixedly connecting the axial magnetic bearing assembly. In terms of the specific assembly process, the following steps can be adopted:

[0032] First, the front bearing assembly 201 is fixed to the compressor housing through the stopper and screws, the axial positioning barrel section 22 is heat-shrink-fitted on the rotating shaft 1, and fits tightly with the shaft shoulder of the rotating shaft 1. After cooling, the radial and axial fixation of the axial positioning barrel section 22 is achieved. Then, the radial positioning barrel section 21 is heat-shrink-fitted on the rotating shaft 1, and fits tightly with the axial positioning barrel section 22. After cooling, the radial and axial fixation of the radial positioning barrel section 21 is achieved. The thrust plate 3 is heat-shrink-fitted on the radial positioning barrel section 21, and fits tightly with the axial positioning barrel section 22. After cooling, the radial and axial fixation of the thrust plate 3 is achieved to form a whole shaft. The whole shaft is from the right side to the left side (the direction is Figure 3 The rear bearing assembly 202 is rotated from right to left on the front bearing assembly 201 and fixed to the compressor housing by means of stopper fit and screws to complete the installation and fixation of the axial bearing thrust plate structure. The control system achieves suspension control of the axial freedom of the entire shaft by regulating the left and right suction of the front bearing assembly 201 and the rear bearing assembly 202 on the thrust plate 3.

[0033] 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.

[0034] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention. The above are only preferred embodiments 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, and these improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. A rotating shaft assembly, characterized in that: The rotary shaft (1) comprises a first shaft section (11), a positioning sleeve (2) being sleeved on the first shaft section (11), the positioning sleeve (2) having a radial positioning sleeve section (21) being heat-fitted with the first shaft section (11) by interference fit, and a thrust plate (3) being heat-fitted on the outer periphery of the radial positioning sleeve section (21); the rotary shaft (1) further comprises a second shaft section (12), the first shaft section (11) and the second shaft section (12) being arranged adjacent to each other along the axial direction of the rotary shaft (1), the diameter of the first shaft section (11) being smaller than the diameter of the second shaft section (12) so as to be spaced apart from each other. A shaft shoulder is formed at the adjacent position; the positioning sleeve (2) also has an axial positioning barrel section (22) abutting against the shaft shoulder; the thrust plate (3) abuts against the axial positioning barrel section (22) on the side facing the shaft shoulder; the outer diameter of the radial positioning barrel section (21) is smaller than the outer diameter of the axial positioning barrel section (22); the radial positioning barrel section (21) and the axial positioning barrel section (22) are respectively independent barrels; the thermal expansion coefficient of the material of the thrust plate (3) is greater than the thermal expansion coefficient of the material of the radial positioning barrel section (21); and the positioning sleeve (2) is made of a non-magnetic material or a weakly magnetic material.

2. A rotating shaft axial magnetic suspension positioning structure, comprising a rotating shaft assembly and an axial magnetic bearing assembly (200), wherein the axial magnetic bearing assembly (200) is capable of applying an axial force to the rotating shaft assembly, and is characterized in that: The rotating shaft assembly is the rotating shaft assembly according to claim 1.

3. The shaft axial magnetic suspension positioning structure according to claim 2 is characterized in that: The axial magnetic bearing assembly (200) comprises a front bearing assembly (201) and a rear bearing assembly (202), wherein the front bearing assembly (201) and the rear bearing assembly (202) are arranged opposite to each other, and the front bearing assembly (201) and the rear bearing assembly (202) are respectively located at opposite ends of the thrust plate (3).

4. A compressor, characterized in that: It includes the rotating shaft axial magnetic suspension positioning structure described in claim 2 or 3.

5. An air conditioner, characterized in that: Comprising the compressor as claimed in claim 4.

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