Dynamic and static pressure coupling liquid suspension bearing and liquid suspension centrifugal compressor

Abstract

The invention is suitable for the technical field of refrigeration equipment, and provides a dynamic and static pressure coupling liquid suspension bearing and a liquid suspension centrifugal compressor, and the dynamic and static pressure coupling liquid suspension bearing comprises a dynamic and static pressure coupling liquid suspension bearing assembly, the dynamic and static pressure coupling liquid suspension bearing assembly comprises a first-stage liquid suspension bearing body, a second-stage liquid suspension bearing body, a first-stage liquid suspension bearing seat, a second-stage liquid suspension bearing seat, a first-stage bearing liquid suspension lubricating medium inlet, a second-stage bearing liquid suspension lubricating medium inlet, a liquid suspension bearing refrigerant static pressure cavity and a liquid suspension bearing annular static pressure groove. The invention discloses a liquid suspension bearing spiral dynamic pressure groove and a liquid suspension bearing pressurization micropore. High-efficiency, low-friction and self-cooling oil-free suspension is achieved through dynamic and static pressure coupling of the liquid refrigerant, the reliability and energy efficiency of the compressor are greatly improved, and a new oil-free path with high cost performance is provided.

Description

Technical Field

[0001] The present invention belongs to the technical field of refrigeration equipment, and in particular relates to a dynamic and static pressure coupled liquid suspension bearing and a liquid suspension centrifugal compressor. Background Art

[0002] In recent years, with the development of oil-free support technologies such as magnetic bearings and air bearings, the energy efficiency of oil-free suspended chillers has been significantly improved compared to traditional oil-lubricated units.

[0003] However, various suspension technologies still have many limitations: magnetic bearings have a complex structure, high manufacturing costs, and complex and sophisticated control systems, which pose challenges to the stability and long-term reliability of the equipment; although air bearings have a relatively simple structure and low cost, their gas carrying capacity is limited, and the main shaft is prone to direct contact friction during start-up, shutdown or sudden power outages, which affects its service life. Currently, they are mainly limited to applications in small cooling capacity models.

[0004] Furthermore, both magnetic and air suspension technologies require a certain suspension gap to prevent eccentric friction on the spindle. This gap is difficult to control and limits sealing, hindering further efficiency improvements. Furthermore, both technologies have shortcomings in cooling the bearings themselves.

[0005] Therefore, in view of the above situation, there is an urgent need to develop a dynamic and static pressure coupled liquid suspension bearing and a liquid suspension centrifugal compressor to overcome the shortcomings in current practical applications. Summary of the Invention

[0006] The object of the present invention is to provide a dynamic and static pressure coupled liquid suspension bearing and a liquid suspension centrifugal compressor, aiming to solve the problems mentioned in the above background technology.

[0007] The present invention is achieved as follows: a dynamic and static pressure coupled liquid suspension bearing includes a dynamic and static pressure coupled liquid suspension bearing assembly, wherein the dynamic and static pressure coupled liquid suspension bearing assembly includes a first-level liquid suspension bearing body, a second-level liquid suspension bearing body, a first-level liquid suspension bearing seat, a second-level liquid suspension bearing seat, a first-level bearing liquid suspension lubrication medium inlet, a second-level bearing liquid suspension lubrication medium inlet, a liquid suspension bearing refrigerant static pressure cavity, a liquid suspension bearing annular static pressure groove, a liquid suspension bearing spiral dynamic pressure groove, and a liquid suspension bearing pressurization microhole;

[0008] The first-stage liquid suspension bearing body and the second-stage liquid suspension bearing body are respectively combined with the first-stage liquid suspension bearing seat and the second-stage liquid suspension bearing seat to form a liquid suspension bearing refrigerant static pressure cavity, and the first-stage bearing liquid suspension lubrication medium inlet and the second-stage bearing liquid suspension lubrication medium inlet are connected to the liquid suspension bearing refrigerant static pressure cavity;

[0009] The annular static pressure groove of the liquid suspension bearing is arranged in the inner wall of the primary liquid suspension bearing body and the secondary liquid suspension bearing body, and is axially uniformly arranged.

[0010] The spiral dynamic pressure groove of the liquid suspension bearing is arranged in the inner wall of the primary liquid suspension bearing body and the secondary liquid suspension bearing body, and is radially uniformly arranged, and the spiral dynamic pressure groove of the liquid suspension bearing forms an included angle of 15-20° with the annular static pressure groove of the liquid suspension bearing.

[0011] The pressure-increasing micro-hole of the liquid suspension bearing is arranged at the intersection of the annular static pressure groove of the liquid suspension bearing and the spiral dynamic pressure groove of the liquid suspension bearing, and the pressure-increasing micro-hole of the liquid suspension bearing communicates the refrigerant static pressure cavity of the liquid suspension bearing, the annular static pressure groove of the liquid suspension bearing and the spiral dynamic pressure groove of the liquid suspension bearing.

[0012] The initial pressure-increasing pressure of the liquid refrigerant when entering the refrigerant static pressure cavity of the liquid suspension bearing through the primary bearing liquid floating lubricating medium inlet and the secondary bearing liquid floating lubricating medium inlet is 8-12 Bar.

[0013] The primary liquid suspension bearing body and the primary liquid suspension bearing seat combination, and the secondary liquid suspension bearing body and the secondary liquid suspension bearing seat combination respectively constitute a radial bearing.

[0014] The back of the primary liquid suspension bearing body and the secondary liquid suspension bearing body is provided with a cavity, and the cavity is combined with the primary liquid suspension bearing seat and the secondary liquid suspension bearing seat to form a refrigerant static pressure cavity of the liquid suspension bearing.

[0015] In a further technical solution, the included angle between the spiral dynamic pressure groove of the liquid suspension bearing and the annular static pressure groove of the liquid suspension bearing is in the range of 15-20°, and the size of the included angle is determined according to the load size.

[0016] Another object of the present application is a liquid suspension centrifugal compressor, comprising a main shaft, a motor rotor, a motor stator, a compressor motor shell, a primary centrifuge assembly, a secondary centrifuge assembly, a thrust disc assembly and the dynamic-static pressure coupling liquid suspension bearing.

[0017] The motor rotor is fixedly sleeved in the middle part of the main shaft, and the motor stator is fixed in the compressor motor shell corresponding to the motor rotor, to jointly constitute a driving force member.

[0018] The primary centrifuge assembly and the secondary centrifuge assembly are respectively arranged at both ends of the main shaft to constitute a pneumatic member, and the driving force member provides radial rotary driving for the pneumatic member through the main shaft.

[0019] The dynamic-static pressure coupling liquid suspension bearing is arranged between the motor rotor and the pneumatic member on both sides, and is used for providing radial suspension support for the main shaft.

[0020] The thrust plate assembly is arranged between the secondary centrifuge impeller and the secondary liquid suspension bearing seat, and adopts the liquid refrigerant static pressure scheme to achieve axial force balance;

[0021] Wherein, the first-stage centrifuge assembly includes a first-stage centrifuge volute, a first-stage centrifuge impeller and a first-stage centrifuge seal, wherein the first-stage centrifuge impeller is arranged in the first-stage centrifuge volute, and the first-stage centrifuge seal is used to provide sealing for the pneumatic components;

[0022] The secondary centrifuge assembly includes a secondary centrifuge volute, a secondary centrifuge impeller and a secondary centrifuge seal. The secondary centrifuge impeller is arranged in the secondary centrifuge volute, and the secondary centrifuge seal is used to provide sealing for the pneumatic components.

[0023] It also includes a stator cooler, which is arranged on the inner wall of the compressor motor housing and corresponds to the motor stator. A stator cooler cooling medium circulation channel is provided inside the stator cooler, and a stator cooler cooling medium inlet and a stator cooler cooling medium outlet are respectively provided at both ends of the stator cooler cooling medium circulation channel.

[0024] According to a further technical solution, the thrust plate assembly includes a thrust plate and a thrust bearing body that are matched with each other.

[0025] A further technical solution is that a compressor cooling lubrication medium outlet is provided at the bottom of the compressor motor housing; the liquid refrigerant enters the motor cavity through the gap between the bearing and the main shaft to evaporate and cool the motor rotor, and then flows out from the compressor cooling lubrication medium outlet to the low-pressure side of the system.

[0026] A further technical solution is that before the compressor is started, the supercooled lower temperature liquid refrigerant is pressurized to 8-12 Bar through an external pump, and enters the liquid suspension bearing refrigerant static pressure chamber through the first-stage bearing liquid suspension lubrication medium inlet and the second-stage bearing liquid suspension lubrication medium inlet; after starting, the external pump stops working and the system pressure difference is used to supply liquid to the bearing.

[0027] The present invention provides a dynamic and static pressure coupled liquid suspension bearing and a liquid suspension centrifugal compressor, which have the following beneficial effects:

[0028] The present invention realizes contactless and oil-free suspended operation of the main shaft. Specifically: the liquid refrigerant in the system is used as the suspension medium, and through the synergistic effect of dynamic and static pressure, the bearing load capacity and operation stability are significantly improved, the radial and axial loads are effectively balanced, hard friction during start-up and shutdown and sudden power outages is avoided, and the service life is extended; at the same time, the liquid refrigerant at a lower temperature after supercooling enters the motor cavity to evaporate and cool the motor after providing suspension support, thereby realizing efficient self-cooling; the technical structure is simple, and no complex control system is required, which greatly reduces manufacturing and maintenance costs; the airtight gap is smaller, leakage loss is reduced, and the energy efficiency of the whole machine is improved; compared with magnetic suspension and gas suspension technologies, it has the advantages of high reliability, high efficiency and low cost, and can be expanded to large-capacity cooling units and other rotating machinery applications, creating a new oil-free suspension technology path with outstanding technological advancement and broad market prospects.

[0029] In summary, the present invention utilizes the dynamic and static pressure coupling of liquid refrigerant to achieve high-efficiency, low-friction, self-cooling oil-free suspension, greatly improving the reliability and energy efficiency of the compressor, and providing a new cost-effective oil-free path. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic structural diagram of a liquid-suspended centrifugal compressor provided in an embodiment of the present invention;

[0031] Figure 2 for Figure 1 The structural diagram of the middle part;

[0032] Figure 3 for Figure 1 The structural diagram on the left;

[0033] Figure 4 for Figure 1 The structural diagram on the right;

[0034] Figure 5 A schematic structural diagram of a refrigerant static pressure chamber portion of a liquid suspension bearing in a dynamic-static pressure coupled liquid suspension bearing provided by an embodiment of the present invention;

[0035] Figure 6 This is a structural schematic diagram of the annular static pressure groove and the spiral dynamic pressure groove of the liquid suspension bearing in the dynamic and static pressure coupled liquid suspension bearing provided by an embodiment of the present invention.

[0036] In the figure: 1-main shaft, 2-motor rotor, 3-motor stator, 4-compressor motor housing, 5-stator cooler, 6-first-stage centrifuge assembly, 7-second-stage centrifuge assembly, 8-dynamic and static pressure coupling liquid suspension bearing assembly, 9-thrust plate assembly, 10-compressor cooling and lubricating medium outlet, 501-stator cooler cooling medium inlet, 502-stator cooler cooling medium circulation channel, 503-stator cooler cooling medium outlet, 601-first-stage centrifuge volute, 602-first-stage centrifuge impeller, 603-first-stage centrifuge seal, 701-second-stage centrifuge vortex Shell, 702-secondary centrifuge impeller, 703-secondary centrifuge seal, 801-first-stage liquid suspension bearing body, 802-first-stage liquid suspension bearing seat, 803-first-stage bearing liquid suspension lubrication medium inlet, 804-secondary liquid suspension bearing body, 805-secondary liquid suspension bearing seat, 806-secondary bearing liquid suspension lubrication medium inlet, 807-liquid suspension bearing refrigerant static pressure cavity, 808-liquid suspension bearing annular static pressure groove, 809-liquid suspension bearing spiral dynamic pressure groove, 8010-liquid suspension bearing booster micropore, 901-thrust plate, 902-thrust bearing body. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0038] The specific implementation of the present invention is described in detail below with reference to specific embodiments.

[0039] Example 1

[0040] like Figure 1-6As shown, a dynamic and static pressure coupled liquid suspension bearing provided by an embodiment of the present invention includes a dynamic and static pressure coupled liquid suspension bearing assembly 8, wherein the dynamic and static pressure coupled liquid suspension bearing assembly 8 includes a first-level liquid suspension bearing body 801, a second-level liquid suspension bearing body 804, a first-level liquid suspension bearing seat 802, a second-level liquid suspension bearing seat 805, a first-level bearing liquid suspension lubrication medium inlet 803, a second-level bearing liquid suspension lubrication medium inlet 806, a liquid suspension bearing refrigerant static pressure cavity 807, a liquid suspension bearing annular static pressure groove 808, a liquid suspension bearing spiral dynamic pressure groove 809 and a liquid suspension bearing pressurization micropore 8010. The first-level liquid suspension bearing body 801 and the second-level liquid suspension bearing body 804 are respectively combined with the first-level liquid suspension bearing seat 802 and the second-level liquid suspension bearing seat 805 to form a liquid suspension bearing refrigerant static pressure cavity 807, the first-level bearing liquid suspension lubrication medium inlet 803 and the second-level bearing The liquid-suspended lubricating medium inlet 806 is connected to the liquid-suspended bearing refrigerant static pressure chamber 807. The liquid-suspended bearing annular static pressure grooves 808 are a plurality of annular grooves arranged evenly in the axial direction and are provided on the inner walls of the first-stage liquid-suspended bearing body 801 and the second-stage liquid-suspended bearing body 804. The liquid-suspended bearing spiral dynamic pressure grooves 809 are a plurality of spiral grooves arranged evenly in the radial direction and are provided on the inner walls of the first-stage liquid-suspended bearing body 801 and the second-stage liquid-suspended bearing body 804. The liquid-suspended bearing spiral dynamic pressure grooves 809 and the liquid-suspended bearing annular static pressure grooves 808 form an angle of 15 to 20 degrees. The liquid-suspended bearing pressurizing micropores 8010 are provided at the intersection of the liquid-suspended bearing annular static pressure grooves 808 and the liquid-suspended bearing spiral dynamic pressure grooves 809, and the liquid-suspended bearing pressurizing micropores 8010 communicate with the liquid-suspended bearing refrigerant static pressure chamber 807, the liquid-suspended bearing annular static pressure grooves 808 and the liquid-suspended bearing spiral dynamic pressure grooves 809.

[0041] The initial boost pressure of the supercooled lower temperature liquid refrigerant when entering the liquid suspension bearing refrigerant static pressure chamber 807 through the first-stage bearing liquid suspension lubrication medium inlet 803 and the second-stage bearing liquid suspension lubrication medium inlet 806 is 8 to 12 Bar.

[0042] The combination of the first-stage liquid suspension bearing body 801 and the first-stage liquid suspension bearing seat 802, and the combination of the second-stage liquid suspension bearing body 804 and the second-stage liquid suspension bearing seat 805, form two radial bearings. The first-stage liquid suspension bearing body 801 and the second-stage liquid suspension bearing body 804 are provided with cavities on their backs, which are respectively combined with the first-stage liquid suspension bearing seat 802 and the second-stage liquid suspension bearing seat 805 to form a liquid suspension bearing refrigerant static pressure chamber 807.

[0043] Example 2

[0044] like Figure 1-6As shown, a liquid-suspended centrifugal compressor provided by one embodiment of the present invention includes a main shaft 1, a motor rotor 2, a motor stator 3, a compressor motor housing 4, a first-stage centrifuge assembly 6, a second-stage centrifuge assembly 7, a thrust plate assembly 9, and the dynamic-static coupling liquid suspension bearing. The motor rotor 2 is fixedly mounted in the middle of the main shaft 1, and the motor stator 3 is fixed in the compressor motor housing 4 corresponding to the motor rotor 2, together forming a driving force component to provide rotational power for the compressor. The first-stage centrifuge assembly 6 and the second-stage centrifuge assembly 7 are respectively arranged at both ends of the main shaft 1 to form a pneumatic component. The driving force component provides radial rotational drive to the pneumatic component through the main shaft 1. The dynamic-static coupling liquid suspension bearing is arranged between the two sides of the motor rotor 2 and the pneumatic component to provide radial suspension support for the main shaft 1; the thrust plate assembly 9 is arranged between the second-stage centrifuge impeller 702 and the second-stage liquid suspension bearing seat 805, and adopts a liquid refrigerant static pressure solution to achieve axial force balance.

[0045] The first-stage centrifuge assembly 6 includes a first-stage centrifuge volute 601, a first-stage centrifuge impeller 602, and a first-stage centrifuge seal 603. The first-stage centrifuge impeller 602 is disposed in the first-stage centrifuge volute 601, and the first-stage centrifuge seal (603) is used to provide a seal for the pneumatic components. The second-stage centrifuge assembly 7 includes a second-stage centrifuge volute 701, a second-stage centrifuge impeller 702, and a second-stage centrifuge seal 703. The second-stage centrifuge impeller 702 is disposed in the second-stage centrifuge volute 701, and the second-stage centrifuge seal 703 is used to provide a seal for the pneumatic components. The main shaft 1 drives the first-stage centrifuge impeller 602 and the second-stage centrifuge impeller 702 to rotate to achieve gas compression, and the first-stage centrifuge seal 603 and the second-stage centrifuge seal 703 ensure airtightness.

[0046] The thrust plate assembly 9 includes a thrust plate 901 and a thrust bearing body 902 that are matched together, and uses a liquid refrigerant static pressure solution to balance the axial force.

[0047] The compressor also includes a stator cooler 5, which is located on the inner wall of the compressor motor housing 4 and corresponds to the motor stator 3. A stator cooler cooling medium circulation channel 502 is provided within the stator cooler 5. A stator cooler cooling medium inlet 501 and a stator cooler cooling medium outlet 503 are provided at either end of the stator cooler cooling medium circulation channel 502. Cooling medium enters the stator cooler cooling medium inlet 501, circulates through the stator cooler cooling medium circulation channel 502, and flows out of the stator cooler cooling medium outlet 503, removing heat generated by the operation of the driving force components. A compressor cooling lubricant outlet 10 is also provided at the bottom of the compressor motor housing 4. Liquid refrigerant enters the motor cavity through the gap between the bearing and the shaft, evaporates and cools the motor rotor 2, and then flows out of the compressor cooling lubricant outlet 10 to the low-pressure side of the system.

[0048] Before the compressor is started, the subcooled, lower-temperature liquid refrigerant is pressurized to 8-12 bar using an external pump. It then enters the liquid suspension bearing refrigerant static pressure chamber 807 through the first-stage bearing liquid suspension lubrication medium inlet 803 and the second-stage bearing liquid suspension lubrication medium inlet 806, respectively. The liquid refrigerant further flows through the liquid suspension bearing pressurization micropores 8010 into the axially arranged annular liquid suspension bearing static pressure grooves 808 and radially arranged helical liquid suspension bearing dynamic pressure grooves 809, pre-set on the bearing's inner wall. The annular liquid suspension bearing static pressure grooves 808 and the helical liquid suspension bearing dynamic pressure grooves 809 form an angle of 15-20° (this angle is determined by the load), thus providing stable static pressure suspension support for the main shaft 1 before startup.

[0049] After startup, due to the high and low pressure differential between the evaporator and condenser, the external pump stops working, and the system pressure differential is used to supply liquid to the bearings. Driven by the high-speed rotation of the main shaft 1, the liquid refrigerant is forced to flow into the spiral dynamic pressure groove 809 of the liquid suspension bearing, forming a relatively high-pressure dynamic self-balancing pressure support along the direction of rotation of the main shaft 1, counteracting the radial fluctuations generated by the load changes during operation of the main shaft 1 and the instantaneous changes in the electromagnetic force of the motor. At the same time, the liquid refrigerant is still affected by the static pressure, forming a dynamic and static pressure coupling mechanism to ensure stable suspension. This mechanism makes the unit operation more stable and can effectively offset the gravity exerted on the main shaft 1 during operation, the electromagnetic force between the motor rotor 2 and the motor stator 3, and the unbalanced forces caused by fluctuations in the compressor operating conditions.

[0050] A thrust plate assembly 9 is installed between the secondary centrifuge impeller 702 and the secondary liquid-suspended bearing seat 805. The assembly includes a thrust plate 901 and a thrust bearing body 902. A liquid refrigerant static pressure solution is adopted to balance the axial force exerted on the main shaft 1 by the pressure of the liquid refrigerant, thereby achieving axial force balance.

[0051] Furthermore, after providing suspension support for the bearings, the liquid refrigerant enters the motor cavity through the tiny gap between the bearings and the main shaft 1. During evaporation within the motor cavity, it absorbs heat and cools the motor rotor 2. Subsequently, the gaseous refrigerant exits the compressor through the compressor cooling and lubricating medium outlet 10, located at the bottom of the compressor motor housing 4, and enters the next stage of the system. In other words, the liquid refrigerant enters the motor cavity through the gap between the bearings and the shaft, cools the motor rotor 2, and then flows from the compressor cooling and lubricating medium outlet 10 to the low-pressure side of the system due to the pressure difference.

[0052] Through the above process, contactless suspension of the main shaft 1 using liquid refrigerant as the medium is achieved, effectively avoiding the disadvantages of existing magnetic suspension bearings and air suspension bearings (high manufacturing cost, complex control and risk of hard friction due to sudden power failure). Compared with air suspension, the airtight gap can be made smaller, which improves the efficiency of the compressor. The greatly improved suspension force can expand the application of larger units and avoid hard friction damage during startup and shutdown, thus pioneering a new oil-free suspension bearing solution.

[0053] In addition, the present invention realizes contactless suspension of the main shaft 1 through dynamic and static pressure coupling of liquid refrigerant, and the liquid refrigerant can be replaced with other ultra-low viscosity liquid media, which can be expanded to other rotary bearing application scenarios.

[0054] The above embodiments of the present invention provide a dynamic and static pressure coupled liquid suspension bearing and a liquid suspension centrifugal compressor, which effectively overcomes many technical bottlenecks in the application of traditional magnetic suspension and air suspension bearings in oil-free centrifugal chillers and has significant comprehensive performance advantages.

[0055] Compared to magnetic levitation bearing technology, the present invention has a simpler structure and does not require a complex electromagnetic control system. This significantly reduces manufacturing costs, reduces potential failure points, improves system reliability and operational stability, and significantly reduces equipment maintenance requirements and operating costs. Because liquid refrigerant is used as the suspension medium, its viscosity is much higher than that of gas. Combined with the dynamic and static pressure coupling design, a smaller airtight gap is achieved, effectively reducing the leakage loss of refrigerant in the gap between the main shaft 1 and the bearing, thereby improving the energy efficiency of the entire machine. In addition, while achieving the suspension of the main shaft 1, the liquid refrigerant can directly participate in the cooling of the bearing, using the refrigeration cycle itself to remove heat, achieving efficient and reliable heat dissipation, and solving the problem of bearing temperature rise.

[0056] Compared with air suspension bearing technology, the present invention utilizes the higher viscosity of liquid refrigerant and the dynamic and static pressure collaborative bearing mechanism to significantly improve the bearing's load-bearing capacity and operational stability, avoids hard contact friction between the main shaft 1 and the bearing under operating conditions such as start-stop and power outages, and extends its service life. At the same time, the "float first, then rotate" operating mode ensures that the main shaft 1 establishes a stable liquid film before startup, further ensuring frictionless operation. The higher suspension force also gives this technology the potential to expand its application to large-capacity centrifugal compressors, breaking through the application limitations of existing air suspension technology in power and capacity.

[0057] In summary, the present invention combines high energy efficiency, high reliability, low cost, good cooling performance and broad application adaptability while achieving completely oil-free operation. It effectively solves the common problems of magnetic levitation and air levitation technologies in structural complexity, control difficulty, insufficient air tightness, weak cooling capacity and start-stop wear, and significantly improves the overall performance of the oil-free centrifugal compressor. It has outstanding technological advancement and broad market application prospects.

[0058] The control, model, and circuit connection of each component are not specifically limited and can be flexibly configured in actual applications. The circuits, electronic components, and modules involved are all prior art and can be fully implemented by those skilled in the art. Needless to say, the content protected by this invention does not involve improvements to the software and methods.

[0059] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0060] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A hydrostatic coupling liquid suspension bearing, comprising a hydrostatic coupling liquid suspension bearing assembly (8), characterized in that: The dynamic-static coupling liquid suspension bearing assembly (8) comprises a first-level liquid suspension bearing body (801), a second-level liquid suspension bearing body (804), a first-level liquid suspension bearing seat (802), a second-level liquid suspension bearing seat (805), a first-level bearing liquid suspension lubricating medium inlet (803), a second-level bearing liquid suspension lubricating medium inlet (806), a liquid suspension bearing refrigerant static pressure cavity (807), a liquid suspension bearing annular static pressure groove (808), a liquid suspension bearing spiral dynamic pressure groove (809), and a liquid suspension bearing pressurization micropore (8010); The first-stage liquid suspension bearing body (801) and the second-stage liquid suspension bearing body (804) are respectively combined with the first-stage liquid suspension bearing seat (802) and the second-stage liquid suspension bearing seat (805) to form a liquid suspension bearing refrigerant static pressure chamber (807); the first-stage bearing liquid suspension lubricating medium inlet (803) and the second-stage bearing liquid suspension lubricating medium inlet (806) are in communication with the liquid suspension bearing refrigerant static pressure chamber (807); The liquid suspension bearing annular static pressure grooves (808) are a plurality of annular grooves arranged axially and provided on the inner walls of the first-stage liquid suspension bearing body (801) and the second-stage liquid suspension bearing body (804); The liquid suspension bearing spiral dynamic pressure grooves (809) are a plurality of radially evenly arranged spiral grooves, and are provided on the inner walls of the first-stage liquid suspension bearing body (801) and the second-stage liquid suspension bearing body (804). The liquid suspension bearing spiral dynamic pressure grooves (809) and the liquid suspension bearing annular static pressure grooves (808) form an angle of 15 to 20 degrees. The liquid suspension bearing pressurization micropore (8010) is provided at the intersection of the liquid suspension bearing annular static pressure groove (808) and the liquid suspension bearing spiral dynamic pressure groove (809), and the liquid suspension bearing pressurization micropore (8010) is connected to the liquid suspension bearing refrigerant static pressure chamber (807), the liquid suspension bearing annular static pressure groove (808) and the liquid suspension bearing spiral dynamic pressure groove (809); The initial boost pressure of the liquid refrigerant when it enters the liquid suspension bearing refrigerant static pressure chamber (807) through the first-stage bearing liquid suspension lubrication medium inlet (803) and the second-stage bearing liquid suspension lubrication medium inlet (806) is 8 to 12 Bar; The combination of the first-stage liquid suspension bearing body (801) and the first-stage liquid suspension bearing seat (802), and the combination of the second-stage liquid suspension bearing body (804) and the second-stage liquid suspension bearing seat (805) respectively constitute radial bearings; The first-stage liquid suspension bearing body (801) and the second-stage liquid suspension bearing body (804) are provided with cavities on their backs, and are respectively combined with the first-stage liquid suspension bearing seat (802) and the second-stage liquid suspension bearing seat (805) to form a liquid suspension bearing refrigerant static pressure cavity (807).

2. The dynamic and static pressure coupled liquid suspension bearing according to claim 1, characterized in that: The included angle between the liquid suspension bearing spiral dynamic pressure groove (809) and the liquid suspension bearing annular static pressure groove (808) is within the range of 15 to 20 degrees, and the size of the included angle is determined according to the load size.

3. A liquid-suspended centrifugal compressor, comprising a main shaft (1), a motor rotor (2), a motor stator (3), a compressor motor housing (4), a first-stage centrifuge assembly (6), a second-stage centrifuge assembly (7), a thrust plate assembly (9), and the dynamic-static pressure coupled liquid-suspended bearing according to any one of claims 1 to 2; The motor rotor (2) is sleeved and fixed on the middle of the main shaft (1), and the motor stator (3) is fixed in the compressor motor housing (4) corresponding to the motor rotor (2), and together they constitute a driving force component, which is characterized by: The first-stage centrifuge assembly (6) and the second-stage centrifuge assembly (7) are respectively arranged at both ends of the main shaft (1) to form a pneumatic component, and the driving force component provides radial rotation drive for the pneumatic component through the main shaft (1); The dynamic and static pressure coupled liquid suspension bearing is arranged between the two sides of the motor rotor (2) and the pneumatic component, and is used to provide radial suspension support for the main shaft (1); The thrust plate assembly (9) is arranged between the secondary centrifuge impeller (702) and the secondary liquid suspension bearing seat (805), and adopts a liquid refrigerant static pressure solution to achieve axial force balance; The first-stage centrifuge assembly (6) comprises a first-stage centrifuge volute (601), a first-stage centrifuge impeller (602), and a first-stage centrifuge seal (603), wherein the first-stage centrifuge impeller (602) is arranged in the first-stage centrifuge volute (601), and the first-stage centrifuge seal (603) is used to provide sealing for the pneumatic components; The secondary centrifuge assembly (7) comprises a secondary centrifuge volute (701), a secondary centrifuge impeller (702) and a secondary centrifuge seal (703), wherein the secondary centrifuge impeller (702) is arranged in the secondary centrifuge volute (701), and the secondary centrifuge seal (703) is used to provide sealing for the pneumatic components; The invention also includes a stator cooler (5), which is arranged on the inner wall of the compressor motor housing (4) and corresponds to the motor stator (3). A stator cooler cooling medium circulation channel (502) is provided inside the stator cooler (5), and a stator cooler cooling medium inlet (501) and a stator cooler cooling medium outlet (503) are respectively provided at both ends of the stator cooler cooling medium circulation channel (502).

4. The liquid-suspended centrifugal compressor according to claim 3, characterized in that: The thrust disc assembly (9) comprises a thrust disc (901) and a thrust bearing body (902) that are arranged in a coordinated manner.

5. The liquid-suspended centrifugal compressor according to claim 3, characterized in that: The bottom of the compressor motor housing (4) is provided with a compressor cooling lubricating medium outlet (10); The liquid refrigerant enters the motor cavity through the gap between the bearing and the main shaft (1) to evaporate and cool the motor rotor (2), and then flows out from the compressor cooling lubricating medium outlet (10) to the low-pressure side of the system.

6. The liquid-suspended centrifugal compressor according to claim 5, characterized in that: Before the compressor is started, the subcooled lower temperature liquid refrigerant is pressurized to 8-12 Bar by an external pump and enters the liquid suspension bearing refrigerant static pressure chamber (807) through the first-stage bearing liquid suspension lubrication medium inlet (803) and the second-stage bearing liquid suspension lubrication medium inlet (806); After starting up, the external pump stops working and the bearing is supplied with fluid by the system pressure difference.

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