Compressor

Abstract

The present application provides a compressor. The compressor includes a drive motor and a wind wheel (1). The drive motor includes a housing (2) and a rotor (3). The rotor (3) is rotatably arranged in the housing (2). The wind wheel (1) is mounted at the first end of the rotor (3). A thrust disc (4) is further arranged at the first end of the rotor (3). An axial air bearing is arranged between the thrust disc (4) and the wind wheel (1). The axial air bearing is fixedly arranged relative to the housing (2). An air gap is formed between the first end of the axial air bearing and the wind wheel (1), and an air gap is formed between the second end of the axial air bearing and the thrust disc (4). According to the compressor of the present application, the tolerance accumulation generated by the part fit between the axial air bearings can be reduced, and the effective working clearance can be more accurately guaranteed.

Description

Technical Field

[0001] This application relates to the field of air compression technology, and more particularly to a compressor. Background Art

[0002] During the frequency conversion adjustment of a centrifugal compressor, as the power increases, the outlet pressure gradually increases. After the centrifugal compressor compresses the gas, a high pressure is formed in the pneumatic cavity. The pressure difference between the high pressure on the back of the impeller and the atmospheric pressure at the suction port causes an axial force along the impeller forward on the entire shafting.

[0003] For this reason, an existing air suspension centrifugal compressor uses double radial air suspension bearings and double axial air suspension bearings for five-degree-of-freedom support operation. Among them, the front and rear radial bearings are distributed on both sides of the motor stator, and the front and rear axial bearings are distributed on both sides of the thrust disk. The axial air suspension bearing has very strict requirements for the effective working clearance with the thrust surface during its operation, and its effective working clearance is basically in the μm level, which will directly affect the load-bearing performance and bearing life of the axial air suspension bearing. The compressor integration scheme adopted requires very strict requirements for the thickness of the thrust disk and the dimensions of each positioning step surface of the front and rear axial bearing assemblies to ensure the effective working clearance of the axial air suspension bearing. However, too many parts assembly will lead to tolerance accumulation, making it impossible to ensure the effective working clearance of the axial air suspension bearing. Summary of the Invention

[0004] Therefore, the technical problem to be solved by this application is to provide a compressor that can reduce the tolerance accumulation generated by the part fit between axial air bearings and more accurately ensure the effective working clearance.

[0005] To solve the above problems, this application provides a compressor, including a driving motor and a wind wheel. The driving motor includes a housing and a rotor. The rotor is rotatably arranged in the housing. The wind wheel is installed at the first end of the rotor. A thrust disk is also arranged at the first end of the rotor. An axial air bearing is arranged between the thrust disk and the wind wheel. The axial air bearing is fixedly arranged relative to the housing. An air gap is formed between the first end of the axial air bearing and the wind wheel, and an air gap is formed between the second end of the axial air bearing and the thrust disk.

[0006] Preferably, the axial air bearing includes an annular fixed seat. An annular bearing seat is arranged on the inner peripheral wall of the fixed seat. A front axial bearing is arranged at the first end of the bearing seat, and a rear axial bearing is arranged at the second end of the bearing seat. An air gap is formed between the front axial bearing and the wind wheel, and an air gap is formed between the rear axial bearing and the thrust disk.

[0007] Preferably, the first end of the bearing seat is matched with the inner peripheral wall of the fixed seat to form a first annular groove, and the front axial bearing is installed in the first annular groove.

[0008] Preferably, at least part of the wind wheel is installed in the first annular groove, and an annular sealing fit is formed between the wind wheel and the inner peripheral wall of the fixed seat.

[0009] Preferably, the second end of the bearing seat cooperates with the inner peripheral wall of the fixed seat to form a second annular groove, and the rear axial bearing is installed in the second annular groove.

[0010] Preferably, the diameter of the thrust disc is less than or equal to the diameter of the second annular groove; and / or, at least part of the thrust disc is installed in the second annular groove.

[0011] Preferably, a radial displacement sensor is arranged on the inner peripheral wall of the fixed seat corresponding to the thrust disc.

[0012] Preferably, the wind wheel includes an axial flange extending towards the thrust disc, the thrust disc includes a first positioning surface facing the axial air bearing, the axial flange is arranged on the inner peripheral side of the axial air bearing, and the positioning end surface of the axial flange towards the thrust disc abuts against the first positioning surface.

[0013] Preferably, the first end of the rotor is provided with a mounting shaft, and the wind wheel is mounted on the mounting shaft.

[0014] Preferably, the first end of the rotor is further provided with a positioning boss, the mounting shaft is located on the positioning boss, the diameter of the positioning boss is less than the diameter of the rotor, the diameter of the mounting shaft is less than the diameter of the positioning boss, the thrust disc is mounted on the positioning boss, and the thickness of the positioning boss is less than the thickness of the thrust disc.

[0015] Preferably, the wind wheel housing is provided with a volute, and an impeller diffuser is arranged on one side of the fixed seat facing the volute. The impeller diffuser cooperates with the volute to form a pneumatic flow channel.

[0016] Preferably, the impeller diffuser is a vaneless diffuser, and a mounting step is arranged on the fixed seat, and the volute is mounted on the mounting step.

[0017] Preferably, a cooling flow channel is arranged in the axial air bearing. The cooling flow channel includes a first liquid inlet, a second liquid inlet and a flow hole, and the first liquid inlet and the second liquid inlet are communicated through the flow hole.

[0018] Preferably, when the axial air bearing includes a fixed seat and a bearing seat, the first liquid inlet and the second liquid inlet are arranged on the fixed seat, and the flow hole flows through the fixed seat and / or the bearing seat.

[0019] Preferably, there are multiple flow holes. The multiple flow holes are communicated with the first liquid inlet through a first communication channel, the multiple flow holes are communicated with the second liquid inlet through a second communication channel, and the first communication channel and the second communication channel are isolated from each other.

[0020] Preferably, the first liquid passage port extends along the axial direction of the fixed seat, the second liquid passage port extends along the axial direction of the fixed seat, the circulation hole extends along the radial direction of the fixed seat, the first communication channel is arranged on the outer peripheral side of the fixed seat, and the second communication channel is arranged on the outer peripheral side of the fixed seat.

[0021] Preferably, the first communication channel is located on the outer peripheral side of the circulation hole and extends along the circumferential direction of the fixed seat, the second communication channel is located on the outer peripheral side of the circulation hole and extends along the circumferential direction of the fixed seat, the first communication channel is located at the first end of a diameter of the fixed seat, and the second communication channel is located at the second end of the diameter.

[0022] Preferably, the first communication channel forms an open slot on the outer peripheral surface of the fixed seat, and / or the second communication channel forms an open slot on the outer peripheral surface of the fixed seat.

[0023] Preferably, the circulation hole is V-shaped, arc-shaped or linear.

[0024] Preferably, radial air bearings are respectively arranged at both ends of the rotor, and the rotor is rotatably sleeved in the radial air bearings.

[0025] Preferably, the radial air bearing at the first end of the rotor is arranged on the side of the thrust plate away from the axial air bearing, and an axial displacement sensor is arranged on the end surface of the radial air bearing facing the thrust plate.

[0026] The compressor provided by the present application includes a driving motor and a wind wheel. The driving motor includes a housing and a rotor. The rotor is rotatably arranged in the housing. The wind wheel is installed at the first end of the rotor. A thrust plate is further arranged at the first end of the rotor. An axial air bearing is arranged between the thrust plate and the wind wheel. The axial air bearing is fixedly arranged relative to the housing. An air gap is formed between the first end of the axial air bearing and the wind wheel, and an air gap is formed between the second end of the axial air bearing and the thrust plate. By installing the axial air bearing between the thrust plate and the wind wheel, the axial end faces of the thrust plate and the wind wheel facing the axial air bearing form thrust surfaces. At the same time, the front axial air bearing and the rear axial air bearing are concentrated on the bearing mounting seat of an axial air bearing in a back-to-back form, making it easier and more accurate to measure the distance between the two bearing surfaces of the front axial air bearing and the rear axial air bearing, and enabling precise control of the distance between the two bearing surfaces. Therefore, when designing the air gap, only by ensuring the distance between the thrust plate and the wind wheel, the air gaps between the axial air bearing and the thrust plate and between the axial air bearing and the wind wheel can be accurately adjusted. Fewer positioning parameters are involved, fewer parts are required, and the tolerance accumulation caused by part assembly is also smaller. It can reduce the tolerance accumulation generated by the part fit between the axial air bearings and more accurately ensure the effective working clearance. Description of the Drawings

[0027] Figure 1Cross-sectional structure diagram of a compressor according to an embodiment of the present application;

[0028] Figure 2 Cross-sectional structure diagram of a compressor according to another embodiment of the present application;

[0029] Figure 3 is Figure 1 Enlarged structure diagram at the axial air bearing installation position;

[0030] Figure 4 Cross-sectional structure diagram of the axial air bearing of a compressor according to an embodiment of the present application;

[0031] Figure 5 is Figure 4 Cross-sectional structure diagram in the A-A direction of

[0032] Figure 6 Cross-sectional structure diagram of the axial air bearing of a compressor according to another embodiment of the present application;

[0033] Figure 7 Cross-sectional structure diagram of the impeller of a compressor according to an embodiment of the present application;

[0034] Figure 8 Cross-sectional structure diagram of the thrust disc of a compressor according to an embodiment of the present application;

[0035] Figure 9 Cross-sectional structure diagram of the radial air bearing of a compressor according to an embodiment of the present application;

[0036] Figure 10 Cross-sectional structure diagram of the radial air bearing of a compressor according to another embodiment of the present application;

[0037] Figure 11 Cross-sectional structure diagram of the rotor of a compressor according to an embodiment of the present application;

[0038] Figure 12 Assembly structure diagram of the rotor, impeller and axial air bearing of a compressor according to an embodiment of the present application;

[0039] Figure 13 Cross-sectional structure diagram of the volute of a compressor according to an embodiment of the present application.

[0040] The reference numerals are shown as:

[0041] 1. Wind wheel; 2. Housing; 3. Rotor; 4. Thrust disk; 5. Fixed seat; 6. Bearing seat; 7. Front axial bearing; 8. Rear axial bearing; 9. First annular groove; 10. Second annular groove; 11. Radial displacement sensor; 12. Axial flange; 13. First positioning surface; 14. Positioning end face; 15. Mounting shaft; 16. Positioning boss; 17. Volute; 18. Impeller diffuser; 19. Mounting step; 20. First liquid passage port; 21. Second liquid passage port; 22. Flow hole; 23. First communication channel; 24. Second communication channel; 25. Radial air bearing; 26. Axial displacement sensor. Detailed implementation manner

[0042] Refer to Figures 1 to 13 As shown, according to an embodiment of the present application, the compressor includes a driving motor and a wind wheel 1. The driving motor includes a housing 2 and a rotor 3. The rotor 3 is rotatably arranged in the housing 2. The wind wheel 1 is installed at the first end of the rotor 3. A thrust disk 4 is further arranged at the first end of the rotor 3. An axial air bearing is arranged between the thrust disk 4 and the wind wheel 1. The axial air bearing is fixedly arranged relative to the housing 2. An air gap is formed between the first end of the axial air bearing and the wind wheel 1, and an air gap is formed between the second end of the axial air bearing and the thrust disk 4.

[0043] The compressor installs the axial air bearing between the thrust disk and the wind wheel 1, so that the axial end faces of the thrust disk and the wind wheel 1 facing the axial air bearing form thrust surfaces. At the same time, the front axial bearing and the rear axial bearing are concentrated on one axial air bearing in a back-to-back form. The thrust surfaces of the thrust disk and the wind wheel 1 and one axial air bearing are used for axial limit, making it easier and more accurate to measure the distance between the two bearing surfaces of the front axial bearing and the rear axial bearing, and enabling precise control of the distance between the two bearing surfaces. When designing the air gap, only the distance between the thrust disk and the wind wheel 1 needs to be ensured, and the air gaps between the axial air bearing and the thrust disk and between the axial air bearing and the wind wheel 1 can be accurately adjusted. There are fewer positioning parameters, fewer parts, and less tolerance accumulation caused by part assembly, which can reduce the tolerance accumulation generated by the part fit between the axial air bearings and more accurately ensure the effective working gap.

[0044] The axial air bearing includes a bearing mounting seat, which includes an annular fixed seat 5 and an annular bearing seat 6. The annular bearing seat 6 is arranged on the inner peripheral wall of the fixed seat 5. A front axial bearing 7 is provided at the first end of the bearing seat 6, and a rear axial bearing 8 is provided at the second end of the bearing seat 6. An air gap is formed between the front axial bearing 7 and the wind wheel 1, and an air gap is formed between the rear axial bearing 8 and the thrust disc 4. In this embodiment, the front axial bearing and the rear axial bearing are integrated on one bearing seat 6, and the suspension control in two axial directions is formed by using one bearing seat 6. The back surface of the wind wheel 1 is used as a thrust surface, and the thrust surface of the thrust disc 4 is matched with the thrust surface of the wind wheel 1 to form two thrust surfaces for axial limit. Thereby, the number of axial air bearings is reduced, the structure of the axial air bearing is simplified, the overall axial thickness of the axial air bearing can also be reduced, the axial length of the rotor 3 can be reduced, and problems such as the decrease of the natural frequency of the shafting and insufficient design margin caused by the too long axial length of the rotor shafting, and the increase of the volume of the air compressor caused by the too long rotor length can be avoided.

[0045] The first end of the bearing seat 6 is matched with the inner peripheral wall of the fixed seat 5 to form a first annular groove 9, and the front axial bearing 7 is installed in the first annular groove 9. The second end of the bearing seat 6 is matched with the inner peripheral wall of the fixed seat 5 to form a second annular groove 10, and the rear axial bearing 8 is installed in the second annular groove 10.

[0046] The bearing seats are arranged at intervals between the front axial bearing 7 and the rear axial bearing 8, so that the operation of the front axial bearing 7 and the rear axial bearing 8 does not interfere with each other. At the same time, the bearing seat 6 can be matched with the fixed seat 5 to form an annular groove for installing the front axial bearing 7 and the rear axial bearing 8, which is convenient for installing and fixing the front axial bearing 7 and the rear axial bearing 8.

[0047] At least part of the wind wheel 1 is installed into the first annular groove 9 and forms an annular sealing fit with the inner peripheral wall of the fixed seat 5, which can ensure the formation of an annular seal between the fixed seat 5 and the wind wheel 1. At least part of the wind wheel 1 is installed into the first annular groove 9, which can reduce the axial space occupied by the wind wheel 1 for the rotor 3 and make the structure of the entire axial direction of the rotor 3 more compact.

[0048] In an air compressor, the side where the impeller 1 rotates at high speed to compress gas is the high-pressure gas side, i.e., the pneumatic part, while the side that drives the impeller 1 to rotate at high speed is the low-pressure gas side, i.e., the motor side. As is well known, if we want to ensure that the performance of the compressor can meet the required standards, in addition to designing the overall scheme of the compressor well, we also need to control the leakage of the compressed gas, that is, to control the amount of high-pressure gas leaking from the high-pressure side to the low-pressure side during the operation of the compressor. In order to effectively suppress the leakage of high-pressure gas on the high-pressure gas side, in this embodiment, an annular sealing position is designed between the annular peripheral wall of the first annular groove 9 and the outer peripheral wall of the impeller 1. An annular seal is to be arranged at the annular sealing position. The annular seal can be a later-assembled part or can be directly machined after leaving a margin at the annular sealing position. There is no requirement for the sealing structure form of the annular seal, as long as it meets the design and use requirements. The annular seal arranged forms a fit with the annular sealing surface formed by the outer peripheral wall of the impeller 1 or the annular peripheral wall of the first annular groove 9, thus forming the entire annular sealing structure.

[0049] The annular seal can be installed on the outer peripheral surface of the impeller 1 or on the inner peripheral surface of the annular peripheral wall of the first annular groove 9. The specific structure form of the annular seal can be a comb-like structure, and sealing packing is filled in the comb-like structure. The annular rotational seal between the impeller 1 and the fixed seat 5 is achieved through the sealing packing.

[0050] In one embodiment, the diameter of the thrust disk 4 is less than or equal to the diameter of the second annular groove 10. The thrust disk 4 is at least partially installed in the second annular groove 10. By defining the relationship between the diameter of the thrust disk 4 and the diameter of the second annular groove 10, the thrust disk 4 can be accommodated in the second annular groove 10, thereby saving the axial space of the rotor 3 and shortening the required axial length of the rotor 3, making the structure of the compressor more compact. In this embodiment, the distance between the opening end face of the second annular groove 10 and the bearing surface of the rear axial bearing 8 is greater than the sum of the axial thickness of the thrust disk 4 and the air gap, and the thrust disk 4 is completely installed in the second annular groove 10.

[0051] When integrating and assembling the compressor structure as a whole, the insertion of the rotor shaft needs to be considered. The inner diameter of the axial air bearing should not be lower than the diameter of the rotor of the radial air bearing. Basically, all the shafting solutions known to the applicant use axial air bearings at both ends of the thrust disk to axially limit the thrust disk. In addition to the serious tolerance accumulation caused by the large number of assembled parts mentioned above, which is likely to lead to problems in ensuring accuracy, due to the influence of the rotor structure, the inner diameter of the axial air bearing cannot be lower than the diameter of the rotor of the radial air bearing. Therefore, the thrust disk located inside the outer circle of the rotor cannot participate in the mating area with the rear axial bearing. Therefore, in order to ensure that there is enough mating area between the thrust disk and the axial bearing, the diameter of the thrust disk will be increased, which also increases the design size of the thrust disk of the rotor shafting.

[0052] When designing the rotor shafting solution for high-speed and even ultra-high-speed applications, the smaller the outer diameter of the assembled parts, the higher the design strength of the parts, and the more helpful it is to improve the mode of the rotor shafting. Therefore, limited by the rotor diameter, the designed outer diameter of the thrust disk is doomed not to be too small.

[0053] After adopting the solution of the present application, a central axial air bearing is used to arrange the front and rear axial bearings back to back, and is installed in the bearing installation positions of the front and rear axial bearings, that is, in the first annular groove 9 and the second annular groove 10, and is placed between the thrust disk 4 and the wind wheel 1. Therefore, during assembly, the rotor with the thrust disk 4 can be vertically placed first, and then the bearing mounting seat of the central axial air bearing equipped with the front and rear axial bearings can be placed on the thrust disk 4, and then the wind wheel 1 is assembled to the rotor and locked to form an integral assembly, as Figure 12 shown, and then the shaft insertion assembly is carried out. In this way, the shaft insertion of the rotor does not need to pass through the front and rear axial bearings, and the front and rear axial bearings do not need to increase the design size to avoid the rotor, thus realizing the miniaturized design of the shafting parts and ensuring the modal performance and safety margin of the entire shafting.

[0054] A radial displacement sensor 11 is provided on the inner peripheral wall of the fixed seat 5 corresponding to the thrust disk 4, which can detect the radial displacement of the rotor 3 through the thrust disk 4.

[0055] The wind wheel 1 includes an axial flange 12 protruding towards the thrust disk 4. The thrust disk 4 includes a first positioning surface 13 towards the axial air bearing. The axial flange 12 is arranged on the inner peripheral side of the axial air bearing, and the positioning end surface 14 of the axial flange 12 towards the thrust disk 4 abuts against the first positioning surface 13. The axial flange 12 protrudes from the thrust surface of the wind wheel 1 and also protrudes towards the thrust surface of the thrust disk 4, that is, the first positioning surface 13. Therefore, only by ensuring the distance between the positioning end surface 14 of the axial flange 12 and the first positioning surface 13, the mating air gap of the axial air bearing can be accurately adjusted, with a simpler design and more convenient implementation.

[0056] The first end of the rotor 3 is provided with a mounting shaft 15, and the wind wheel 1 is mounted on the mounting shaft 15. The first end of the rotor 3 is further provided with a positioning boss 16. The mounting shaft 15 is located on the positioning boss 16. The diameter of the positioning boss 16 is smaller than the diameter of the rotor 3, and the diameter of the mounting shaft 15 is smaller than the diameter of the positioning boss 16. The thrust disc 4 is mounted on the positioning boss 16. The axial height h1 of the positioning boss 16 is smaller than the thickness of the thrust disc 4, so that the first positioning surface 13 of the thrust disc 4 can be higher than the end surface of the positioning boss 16, avoiding interference of the positioning boss 16 with the fit between the first positioning surface 13 and the positioning end surface 14.

[0057] In a compressor supported by air bearings, the assembly adjustment of the effective working clearance of the axial air bearings is one of the most important processes. The front axial bearing 7 is installed at the front axial bearing 7 installation position on the central bearing mounting seat, and the rear axial bearings 8 are respectively installed at the rear axial bearing 8 installation positions, realizing that the two axial air bearings originally placed on both sides of the thrust disc 4 and respectively installed on two parts are concentrated back-to-back on one part. This makes it easier and more accurate to measure the distance between the bearing surfaces of the installed front axial bearing 7 and the rear axial bearing 8. An effective working clearance is formed between the rear axial bearing 8 and the thrust surface of the thrust disc 4, and an effective working clearance is formed between the front axial bearing 7 and the thrust surface of the wind wheel 1.

[0058] The thrust surfaces of the two axial bearings are respectively distributed on the thrust disc 4 and the wind wheel 1. The material of the wind wheel 1 is preferably alloy steel that can directly serve as a bearing. Considering weight reduction, a wear-resistant alloy steel material layer can be added to the bearing surface as the bearing surface. The thrust disc 4 is directly made of alloy steel. The effective working clearance between the thrust surface of the wind wheel 1 and the thrust surface of the thrust disc 4 and the air axial bearing is ensured by the first positioning surface 13 of the thrust disc 4 and the axial flange height h2 of the wind wheel 1. A certain margin is reserved for the axial flange 12 during the processing of the wind wheel 1. Since both the thrust disc 4 and the wind wheel 1 are precision-machined parts, after accurately measuring the distance between the two bearing surfaces of the axial air bearing and adding the effective working clearance of the axial bearing, the axial flange height h2 can be directly machined in place to ensure that the axial height h1 of the positioning boss 16 of the rotating shaft is lower than the thickness of the thrust disc 4. The outer peripheral surface of the positioning boss 16 serves as the assembly surface for the thrust disc, the end face of the first end of the rotor serves as the positioning surface for the thrust disc, and the outer peripheral surface of the mounting shaft 15 serves as the assembly surface for the impeller, so that the machining accuracy of each assembly surface is within the required range. The inner ring part of the thrust surface of the thrust disc 4 also serves as the installation and positioning surface for the axial flange 12 of the wind wheel 1. Assembling in the order of the rotor 3, the thrust disc 4, the axial air bearing, and the wind wheel 1 can complete the overall assembly of the entire shaft system. In this way, the precise adjustment of the effective working clearance of the axial air bearing can be achieved by machining one dimension of one part (the machining of the axial flange height h2 of the wind wheel 1), which not only optimizes and simplifies the machining process of the parts, but also simplifies the assembly method and adjustment method, and greatly optimizes the process flow.

[0059] A volute 17 is provided on the outer cover of the wind wheel 1. An impeller diffuser 18 is provided on one side of the fixed seat 5 facing the volute 17. The impeller diffuser 18 cooperates with the volute 17 to form a pneumatic flow passage. The impeller diffuser includes a vane diffuser and a vaneless diffuser. In this embodiment, the impeller diffuser 18 is a vaneless diffuser. An installation step 19 is provided on the fixed seat 5, and the volute 17 is installed on the installation step 19.

[0060] The middle bearing mounting seat has a machining allowance left along the axial direction during machining for machining the impeller diffuser 18. Since the impeller diffuser 18 needs to be combined with the volute 17 to form a complete flow passage, when making a split design, the diffuser is generally designed as a plane, and the complex structure is realized on the volute 17. Therefore, the vaneless diffuser only needs to be machined into a plane, and then the impeller diffuser 18 and the volute 17 are assembled to form a complete pneumatic flow passage.

[0061] A cooling flow passage is provided inside the axial air bearing. The cooling flow passage includes a first liquid inlet 20, a second liquid inlet 21, and a flow hole 22. The first liquid inlet 20 and the second liquid inlet 21 are connected through the flow hole 22. The cooling flow passage is filled with a coolant, which can cool the axial air bearing.

[0062] In this embodiment, since the front axial air bearing and the rear axial air bearing are combined into one to form an axial air bearing, the overall thickness of the fixing seat 5 for installing the axial air bearing can be increased without increasing the axial length, so that there is enough axial thickness on both the fixing seat 5 and the bearing seat 6 to set the cooling flow channels, which is convenient for the design of the cooling system.

[0063] When the compressor runs at high speed, the working gap between the thrust disc 4 and the axial air bearing is very small, generally in the order of micrometers. The high-pressure air in such a small gap will generate a large amount of heat due to high-speed friction with the surfaces of the axial air bearing and the thrust disc 4. However, the too-small working gap is not conducive to the heat dissipation of the surfaces of the axial air bearing and the thrust disc 4. After the axial air bearing and the thrust disc 4 are heated, they will undergo thermal expansion deformation in the axial direction. Excessive temperature will cause the thermal expansion amount to squeeze out all the working gaps of the axial air bearing, resulting in a locking situation. The sudden locking of the rotor under high-speed rotation may lead to the scrapping of the entire compressor. If a foil-type axial air bearing is used, there will also be a wear-resistant lubricating coating on its surface. Excessive temperature may cause the wear-resistant lubricating coating to fail or even fall off, which will also cause serious damage to the compressor.

[0064] To address the above possible situations and reduce the temperature of the axial air bearing during operation, the present application provides a cooling flow channel on the central bearing mounting seat. The cooling liquid in the cooling flow channel dissipates the heat generated during the operation of the axial air bearing and the thrust disc 4, thereby effectively reducing the temperature of the axial air bearing during operation.

[0065] When the axial air bearing includes a fixing seat 5 and a bearing seat 6, the first liquid inlet 20 and the second liquid inlet 21 are provided on the fixing seat 5, and the flow hole 22 passes through the fixing seat 5 and / or the bearing seat 6. In this embodiment, the first liquid inlet 20 and the second liquid inlet 21 are provided on the fixing seat 5, and the flow hole 22 passes through the fixing seat 5 and the bearing seat 6, so as to effectively cool the entire bearing mounting seat and reduce the temperature during the operation of the bearing mounting seat.

[0066] There are multiple fluid flow holes 22. The multiple fluid flow holes 22 are connected to the first fluid inlet 20 through the first communication channel 23, and the multiple fluid flow holes 22 are connected to the second fluid inlet 21 through the second communication channel 24. The first communication channel 23 and the second communication channel 24 are isolated from each other. The first communication channel 23 and the second communication channel 24 can only be connected through the fluid flow holes 22, so that the coolant cannot directly enter the second communication channel 24 through the first communication channel 23, or enter the first communication channel 23 through the second communication channel 24. It can only enter one of the communication channels from the liquid inlet, and after distributing the coolant through this communication channel, the coolant evenly enters each fluid flow hole 22, then flows from the fluid flow hole 22 into the other communication channel, and after converging through the other communication channel, it flows out from the liquid outlet, realizing the cooling of the bearing mounting seat.

[0067] The first fluid inlet 20 extends along the axial direction of the fixed seat 5, the second fluid inlet 21 extends along the axial direction of the fixed seat 5, the fluid flow holes 22 extend along the radial direction of the fixed seat 5, the first communication channel 23 is arranged on the outer peripheral side of the fixed seat 5, and the second communication channel 24 is arranged on the outer peripheral side of the fixed seat 5. In another embodiment, the first fluid inlet 20 and the second fluid inlet 21 can also be directly arranged in the radial direction, the first communication channel 23 extends along the circumferential direction, and the second communication channel 24 extends along the circumferential direction, so as to complete the connection of the first fluid inlet 20, the first communication channel 23, the fluid flow holes 22, the second communication channel 24 and the second fluid inlet 21, and realize the design of the cooling flow path.

[0068] The first communication channel 23 is located on the outer peripheral side of the fluid flow hole 22 and extends along the circumferential direction of the fixed seat 5, the second communication channel 24 is located on the outer peripheral side of the fluid flow hole 22 and extends along the circumferential direction of the fixed seat 5. The first communication channel 23 is located at the first end of a diameter of the fixed seat 5, and the second communication channel 24 is located at the second end of this diameter, so that the fluid flow hole 22 can flow through the bearing mounting seat to the greatest extent, perform more effective cooling on the entire bearing mounting seat, and improve the cooling effect.

[0069] In one embodiment, the first communication channel 23 forms an open groove on the outer peripheral surface of the fixed seat 5, and the second communication channel 24 forms an open groove on the outer peripheral surface of the fixed seat 5, which is convenient for the processing of each communication channel. The communication channels are arranged on the mounting step 19 of the fixed seat 5. After the communication channels are opened, the volute 17 can be fixedly arranged on the mounting step 19, and the first communication channel 23 and the second communication channel 24 are sealed through the mating mounting surface of the volute 17. In order to improve the sealing effect, sealing rings or sealing grooves are arranged on both sides of the first communication channel 23 and the second communication channel 24.

[0070] The flow holes 22 are in a V shape, an arc shape or a straight shape, and can be directly machined. The machining method is simple and the machining cost is relatively low. In other embodiments, other forming methods can also be used to form the structures of different flow holes 22, such as serpentine flow holes 22 or zigzag flow holes 22, etc.

[0071] Radial air bearings 25 are respectively arranged at both ends of the rotor 3. The rotor 3 is rotatably sleeved in the radial air bearings 25. The radial air bearings 25 are fixed on the housing 2, and the fixing seat 5 is fixedly installed on the radial air bearings 25.

[0072] The liquid inlet on the fixing seat 5 is communicated with the liquid channels pre-opened at corresponding positions on the compressor liquid-cooled housing 2 and the radial air bearings 25. The outer hole of the liquid inlet is sealed with a rubber ring through a sealing groove to prevent leakage. The inner hole of the liquid inlet is communicated with the communication channel, and the communication channel is further communicated with all the flow holes 22 to form a complete cooling circulation structure. Among them, the communication channel is a ring-shaped semi-open cooling flow channel design, which is convenient for machining. Then, through the sealing grooves and rubber rings on both sides of the communication channel and the annular sealing surface of the volute 17, a complete closed cooling flow channel is formed to prevent the cooling liquid from leaking in the central bearing mounting seat.

[0073] Preferably, with reference to Figure 1 and Figure 4 As shown, when the whole compressor is placed, the compressor is placed and fixed in the horizontal direction of the rotor. The lower liquid inlet is the liquid inlet, and the upper liquid inlet is the liquid outlet. This setting is to use the pressure of the whole machine cooling system of the compressor to press the coolant into the liquid inlet at the bottom of the central bearing mounting seat, so that the coolant fills the entire cooling flow channel and is then pressed out from the liquid outlet, so as to ensure that the coolant can fully contact the cooling flow channel and take away the heat generated during the operation of the axial air bearing to the greatest extent, and maximize the cooling of the axial air bearing on the central bearing mounting seat. The central bearing mounting seat is a key component connecting the motor side and the pneumatic part, and a relief round hole for passing through the rotor is provided in the center. Therefore, the internal flow holes 22 cannot be completely vertically distributed as expected. In this application, the flow holes 22 are designed in a V shape, an arc shape or a straight shape, so that while avoiding the relief round hole, the flow holes 22 can flow through the bearing mounting seat as much as possible, improving the cooling effect. The structural form of the internal flow holes 22 is not limited to the above concentration. For the shape and quantity of the liquid channels, designers can make corresponding designs according to the actual application situation.

[0074] In addition, since the pneumatic part of the air compressor continuously operates to compress air and do work, the temperature in the pneumatic cavity will gradually rise. The increased temperature will be transmitted to the motor side through the metal housing of the air compressor, which is not conducive to the heat dissipation of the motor side of the compressor. The central bearing mount with a circulating cooling channel can serve as a barrier and use its own cooling effect to prevent the heat generated by the pneumatic part from being transmitted to the motor side of the compressor, thereby ensuring the cooling of the motor side of the compressor.

[0075] The radial air bearing 25 at the first end of the rotor 3 is arranged on the side of the thrust plate 4 away from the axial air bearing. An axial displacement sensor 26 is arranged on the end face of the radial air bearing 25 facing the thrust plate 4, which can cooperate with the scheme of arranging the radial displacement sensor 11 on the inner peripheral side of the aforementioned fixed seat 5, and the radial displacement sensor 11 facing the outer peripheral face of the thrust plate 4, so that the detection of the radial and axial displacements of the rotor 3 is carried out through this one component, the thrust plate 4.

[0076] Since the air compressor supported by air bearings belongs to a high-speed and high-precision operating turbomachine, the rotor needs to be monitored in real time during the R & D test stage or some special occasions. By judging the running trajectory of the rotor under different speeds and working conditions, the performance and dynamic stability of the bearings can be determined. In order to realize the dynamic monitoring of the rotor of the air compressor supported by air bearings, this application makes improvements and adjustments on the radial air bearing near the axial air bearing and the central axial bearing seat. First, the size of the axial air bearing near the pneumatic part side is increased, and two counterbores are opened on the axial air bearing near the pneumatic part side as the installation positions for the rotor axial displacement sensor, for arranging the axial displacement sensor 26 to monitor the axial situation generated during the operation of the rotor. And on the inner peripheral wall of the fixed seat 5 of the axial bearing, two symmetrically distributed counterbores or four counterbores distributed in a cross shape are opened along the radial direction as the installation positions for the rotor radial displacement sensor, for arranging the radial displacement sensor 11 to monitor the running trajectory of the axis center of the rotor during operation. At the same time, the outer circle of the thrust plate 4 can be used as the rotor radial displacement monitoring surface after precision machining. Similarly, the end face of the thrust plate 4 that does not cooperate with the axial air bearing can be used as the rotor axial displacement monitoring surface after precision machining. Since both the rotor radial displacement monitoring surface and the rotor axial displacement monitoring surface are arranged on the thrust plate 4, the errors caused by the machining of the rotor shafting parts and the assembly between different shafting parts, as well as the influence caused by the bending deformation of the rotor, can be reduced, and the accuracy of the monitoring can be improved.

[0077] It is easy for those skilled in the art to understand that, on the premise of no conflict, the above-mentioned various advantageous ways can be freely combined and superimposed.

[0078] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application. The above is only the preferred implementation manner of the present application. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the technical principle of the present application, several improvements and variations can still be made, and these improvements and variations should also be regarded as within the protection scope of the present application.

Claims

1. A compressor, characterized in that, It includes a driving motor and a wind wheel (1). The driving motor includes a housing (2) and a rotor (3). The rotor (3) is rotatably arranged in the housing (2). The wind wheel (1) is installed at the first end of the rotor (3). A thrust disc (4) is also arranged at the first end of the rotor (3). An axial air bearing is arranged between the thrust disc (4) and the wind wheel (1). The axial air bearing is fixedly arranged relative to the housing (2). An air gap is formed between the first end of the axial air bearing and the wind wheel (1), and an air gap is formed between the second end of the axial air bearing and the thrust disc (4). The axial air bearing includes an annular fixed seat (5). An annular bearing seat (6) is arranged on the inner peripheral wall of the fixed seat (5). A front axial bearing (7) is arranged at the first end of the bearing seat (6), and a rear axial bearing (8) is arranged at the second end of the bearing seat (6). An air gap is formed between the front axial bearing (7) and the wind wheel (1), and an air gap is formed between the rear axial bearing (8) and the thrust disc (4).

2. The compressor according to claim 1, characterized in that, The first end of the bearing seat (6) cooperates with the inner peripheral wall of the fixed seat (5) to form a first annular groove (9), and the front axial bearing (7) is installed in the first annular groove (9).

3. The compressor according to claim 2, characterized in that, At least part of the wind wheel (1) is installed into the first annular groove (9), and a ring-shaped sealing fit is formed between the wind wheel (1) and the inner peripheral wall of the fixed seat (5).

4. The compressor according to any one of claims 1 to 3, characterized in that, The second end of the bearing seat (6) cooperates with the inner peripheral wall of the fixed seat (5) to form a second annular groove (10), and the rear axial bearing (8) is installed in the second annular groove (10).

5. The compressor according to claim 4, characterized in that, The diameter of the thrust disc (4) is less than or equal to the diameter of the second annular groove (10); and / or, at least part of the thrust disc (4) is installed in the second annular groove (10).

6. The compressor according to claim 4, characterized in that A radial displacement sensor (11) is arranged on the inner peripheral wall of the fixed seat (5) corresponding to the thrust disc (4).

7. The compressor according to any one of claims 1 to 3 and 5 - 6, characterized in that, The wind wheel (1) includes an axial flange (12) extending towards the thrust disc (4). The thrust disc (4) includes a first positioning surface (13) facing the axial air bearing. The axial flange (12) is arranged on the inner peripheral side of the axial air bearing, and the positioning end surface (14) of the axial flange (12) facing the thrust disc (4) abuts against the first positioning surface (13).

8. The compressor according to claim 7, characterized in that, An installation shaft (15) is arranged at the first end of the rotor (3), and the wind wheel (1) is installed on the installation shaft (15).

9. The compressor according to claim 8, wherein A positioning boss (16) is also arranged at the first end of the rotor (3). The installation shaft (15) is located on the positioning boss (16). The diameter of the positioning boss (16) is less than the diameter of the rotor (3). The diameter of the installation shaft (15) is less than the diameter of the positioning boss (16). The thrust disc (4) is installed on the positioning boss (16), and the thickness of the positioning boss (16) is less than the thickness of the thrust disc (4).

10. The compressor according to claim 1, characterized in that, A volute (17) is provided outside the wind wheel (1). An impeller diffuser (18) is provided on one side of the fixed seat (5) facing the volute (17). The impeller diffuser (18) cooperates with the volute (17) to form a pneumatic flow channel.

11. The compressor according to claim 10, wherein, The impeller diffuser (18) is a vaneless diffuser. An installation step (19) is provided on the fixed seat (5), and the volute (17) is installed on the installation step (19).

12. The compressor according to any one of claims 1 to 3, 5, 6, 8 to 11, characterized in that, A cooling flow channel is provided inside the axial air bearing. The cooling flow channel includes a first liquid inlet (20), a second liquid inlet (21) and a flow hole (22). The first liquid inlet (20) and the second liquid inlet (21) are connected through the flow hole (22).

13. The compressor according to claim 12, characterized in that, When the axial air bearing includes a fixed seat (5) and a bearing seat (6), the first liquid inlet (20) and the second liquid inlet (21) are provided on the fixed seat (5), and the flow hole (22) flows through the fixed seat (5) and / or the bearing seat (6).

14. The compressor according to claim 13, wherein, There are multiple flow holes (22). The multiple flow holes (22) are connected to the first liquid inlet (20) through a first communication channel (23). The multiple flow holes (22) are connected to the second liquid inlet (21) through a second communication channel (24). The first communication channel (23) and the second communication channel (24) are isolated from each other.

15. The compressor according to claim 14, characterized in that, The first liquid inlet (20) extends along the axis of the fixed seat (5). The second liquid inlet (21) extends along the axis of the fixed seat (5). The flow hole (22) extends along the radius of the fixed seat (5). The first communication channel (23) is provided on the outer peripheral side of the fixed seat (5). The second communication channel (24) is provided on the outer peripheral side of the fixed seat (5).

16. The compressor according to claim 15, characterized in that, The first communication channel (23) is located on the outer peripheral side of the flow hole (22) and extends along the circumferential direction of the fixed seat (5). The second communication channel (24) is located on the outer peripheral side of the flow hole (22) and extends along the circumferential direction of the fixed seat (5). The first communication channel (23) is located at the first end of a diameter of the fixed seat (5), and the second communication channel (24) is located at the second end of this diameter.

17. The compressor according to claim 15, characterized in that, The first communication channel (23) forms an open slot on the outer peripheral surface of the fixed seat (5), and / or the second communication channel (24) forms an open slot on the outer peripheral surface of the fixed seat (5).

18. The compressor according to claim 13, characterized in that, The flow hole (22) is V-shaped, arc-shaped or linear.

19. The compressor according to any one of claims 1 to 3, 5, 6, 8 to 11, 13 to 18, characterized in that, Radial air bearings (25) are respectively provided at both ends of the rotor (3). The rotor (3) is rotatably sleeved inside the radial air bearings (25).

20. The compressor according to claim 19, wherein, The radial air bearing (25) at the first end of the rotor (3) is provided on the side of the thrust disc (4) away from the axial air bearing. An axial displacement sensor (26) is provided on the end face of the radial air bearing (25) facing the thrust disc (4).

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