Magnetic-liquid coupling suspension mechanical pump with disc type impeller and impeller assembly

Abstract

The invention provides a magnetic-liquid coupling suspension mechanical pump with a disc type impeller and an impeller assembly, the impeller assembly comprises blades, a wheel disc and a wheel shaft, and the wheel shaft is used for being fixedly connected with a rotor assembly of the magnetic-liquid coupling suspension mechanical pump; the wheel disc is arranged at one end of the wheel shaft; the blades are arranged on the wheel disc; wherein at least one wheel disc through hole is formed in the wheel disc, and liquid flows into the periphery of the rotor assembly through the wheel disc through hole to form hydraulic pressure to support the rotor assembly. Through the structural design of the wheel disc, the contact area of the roots of the blades and the wheel disc is increased, the mechanical strength of the blades is remarkably improved, blade deformation and failure caused by high-rotating-speed or high-performance operation are prevented, the reliability of the impeller is improved, meanwhile, through the proportion optimization design of the outer diameter of the wheel disc and the outer diameter of the blades, blade top gap leakage is reduced, and the service life of the impeller is prolonged. The hydraulic efficiency of the pump is improved, hydraulic force can be improved, and full-freedom-degree suspension of the rotor assembly is achieved.

Description

Technical Field

[0001] The present invention belongs to the field of mechanical pumps, and particularly relates to a magnetic fluid coupling suspension mechanical pump with a disc impeller and an impeller assembly. Background Art

[0002] With the rapid development of AI servers, new energy, data centers, etc., the integration of electronic devices is getting higher and higher, and the heat generation per unit area is getting larger and larger. The traditional air-cooled heat dissipation solution cannot meet the higher system requirements, and the development and large-scale application of the active liquid-cooled heat dissipation solution have become inevitable. The mechanical pump is the core component of the liquid-cooled heat dissipation system, and its performance and reliability directly determine the performance and reliability of the system. In addition, as an important research direction of microelectromechanical systems, mechanical pumps are also widely used in fields such as chemical transportation systems, special pumping systems, and medical equipment.

[0003] The mechanical pumps applied in the liquid-cooled heat dissipation industry are contact bearing pumps, which have mechanical friction losses during high-speed rotation, resulting in a working life of the mechanical pump generally being 2 to 3 years, which cannot meet the usage requirements of application scenarios with high reliability requirements (such as the liquid-cooled products in data centers and charging piles having a service life of 10 to 15 years). The key to solving this problem lies in solving bearing wear. Among them, the magnetic suspension bearing technology is one direction, and researchers have designed different forms of magnetic suspension mechanical pumps using the principle of magnetic levitation or the principle of hydraulic levitation. Among them, the magnetic suspension bearing needs to use a sensor to capture the position of the rotor in real time and feedback the position signal to the auxiliary coil, so as to generate a balancing force to make the rotor always in a suspended state. The system structure of this solution is complex, and the system loss is large, with serious heat generation, which is not suitable for the liquid-cooled heat dissipation field. The hydraulic suspension technology can make the rotor achieve full-degree-of-freedom suspension through the hydraulic action of the fluid inside the pump.

[0004] The current hydraulic suspension technology or magnetic fluid hybrid suspension technology in the industry both need to introduce the fluid into the motor using a pressure difference, so as to generate a hydraulic pressure in the motor to provide a suspension effect. However, most of the existing solutions use open impellers so that the liquid in the motor can smoothly enter the central low-pressure area of the pump inlet. However, the blade roots of the open impellers have low strength, and the blades are prone to force deformation and failure during high-speed or high-performance operation of the pump, and the blade gap leakage of the open impellers is large, resulting in low hydraulic efficiency.

[0005] In summary, there is a need for an impeller that can allow the fluid in the central low-pressure area of the pump inlet to enter the motor, while ensuring that the blade roots have sufficient strength, and can reduce the leakage of the tip clearance and improve the hydraulic efficiency. Summary of the Invention

[0006] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a magnetic fluid coupling suspension mechanical pump with a disc impeller and an impeller assembly, so as to solve the problem that existing solutions mostly adopt open impellers so that the liquid in the motor can smoothly enter the central low-pressure area of the pump inlet. However, the blade roots of the open impellers have low strength, and the blades are prone to force deformation and failure during high-speed or high-performance operation of the pump. In addition, the blade gaps of the open impellers have large leakage, resulting in low hydraulic efficiency.

[0007] To achieve the above object and other related objects, the present invention provides an impeller assembly for a magnetic fluid coupling suspension mechanical pump, including: blades, a disc, and a shaft,

[0008] The shaft is used for fixedly connecting with the rotor assembly of the magnetic fluid coupling suspension mechanical pump;

[0009] The disc is arranged at one end of the shaft;

[0010] The blades are arranged on the disc;

[0011] Wherein, at least one through hole is provided on the disc, and the liquid flows through the through hole on the disc to the periphery of the rotor assembly to form a hydraulic pressure to support the rotor assembly.

[0012] In an embodiment of the present invention, the shaft is of a flat structure, including single flat, double flat or multiple flats, and the flat structure is connected with the rotor assembly by interference fit.

[0013] In an embodiment of the present invention, the ratio range of the outer diameter of the disc to the outer diameter of the blade is 0.1-1.5.

[0014] In an embodiment of the present invention, the number of the through holes on the disc is multiple, and they are evenly distributed along the circumferential direction of the disc.

[0015] In an embodiment of the present invention, the disc is of a semi-closed or fully-closed structure.

[0016] In an embodiment of the present invention, a guide convex platform is provided at the bottom of the disc, and the guide convex platform forms a stepped fluid acceleration channel along the direction towards the center position of the disc.

[0017] The present invention also provides a magnetic fluid coupling suspension mechanical pump with a disc impeller, including: a pump cover, an end cover, a housing, a stator assembly, a rotor assembly, and the impeller assembly according to any one of the above embodiments;

[0018] A pump chamber is formed inside the pump cover;

[0019] An inner housing cavity is recessed in the central area of the housing;

[0020] The end cover is located between the pump cover and the housing, and the end cover is provided with circumferential holes;

[0021] The through-hole of the wheel disc of the impeller assembly communicates with the circumferential holes, forming a fluid passage from the pump chamber to the inner housing chamber, enabling the low-pressure liquid in the pump chamber to enter the periphery of the chamber wall of the inner housing chamber and the rotor assembly through the fluid passage;

[0022] The rotor assembly realizes full-degree-of-freedom suspension through the coupling action of liquid pressure and electromagnetic force, where the liquid pressure is generated by the liquid flowing through the through-hole of the wheel disc, and the electromagnetic force is formed by the magnetic field interaction between the stator assembly and the rotor assembly.

[0023] In an embodiment of the present invention, the fluid passage includes:

[0024] The first fluid channel, and the liquid flows into the gap between the rotor assembly and the end cover through the circumferential holes;

[0025] The second fluid channel, and the liquid flows downward through the gap between the wheel shaft and the inner hole of the rotor assembly;

[0026] The third fluid channel, and the liquid is in the gap between the rotor assembly and the bottom of the inner housing chamber of the housing (5) and is centrifugally accelerated in the gap;

[0027] The fourth fluid channel, and the liquid flows back to the first fluid channel through the gap between the rotor assembly and the wall surface of the inner housing chamber of the housing.

[0028] In an embodiment of the present invention, the liquid film in the fourth fluid channel forms a radial support for the rotor assembly, and at the same time, the axial suspension of the rotor assembly is realized by the synergistic action of magnetic pulling force and fluid axial force.

[0029] In an embodiment of the present invention, a spiral return groove is provided between the rotor assembly and the inner wall of the housing, and the pitch of the spiral return groove gradually decreases along the liquid flow direction, which is used to guide the liquid to form a vortex liquid film.

[0030] The present invention has the following beneficial effects:

[0031] Through the structural design of the wheel disc, the present invention increases the contact area between the blade root and the wheel disc, significantly improves the mechanical strength of the blade, prevents the blade from deforming and failing due to high-speed or high-performance operation, improves the reliability of the impeller, and at the same time, through the optimized design of the ratio of the outer diameter of the wheel disc to the outer diameter of the blade, reduces the leakage of the tip clearance, improves the hydraulic efficiency of the pump, is beneficial to the improvement of liquid pressure, enables the rotor assembly to realize full-degree-of-freedom suspension, avoids mechanical friction, prolongs the service life of the mechanical pump, and meets the requirements of high-reliability application scenarios. Description of the Drawings

[0032] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0033] Figure 1 It is a schematic structural diagram of the present invention in one embodiment.

[0034] Figure 2 It is a schematic structural diagram of the end cover of the present invention in one embodiment.

[0035] Figure 3 It is a schematic structural diagram of the semi-closed impeller assembly of the present invention in one embodiment.

[0036] Figure 4 It is a schematic structural diagram of the fully enclosed impeller assembly of the present invention in one embodiment.

[0037] Figure 5 It is a schematic diagram of the fluid channel of the inner shell cavity of the present invention in one embodiment.

[0038] Figure 6 It is a schematic diagram of the axial force on the rotor of the present invention in one embodiment.

[0039] Reference numeral description:

[0040] 1. Pump cover; 2. Impeller assembly; 2a. Blade; 2b. Disk; 2b'. Fully enclosed disk; 2c. Wheel shaft; 2d. Disk through hole; 3. Sealing ring; 4. End cover; 5. Housing; 6. Stator skeleton; 7. Coil winding; 8. Stator core; 9. Rotor sleeve; 10. Rotor; 11. Bush; 12. Driving plate; 13. Rear cover. Specific embodiments

[0041] The following illustrates the embodiments of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0042] It should be noted that the diagrams provided in this embodiment only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0043] Please refer to Figures 1 to 6 As shown, the present invention provides a magnetic fluid coupling suspension mechanical pump with a disc impeller and an impeller assembly to solve the problem that existing solutions mostly use open impellers so that the liquid in the motor can smoothly enter the central low-pressure area of the pump inlet. However, the blade roots of the open impeller have low strength, and the blades are prone to force deformation and failure during high-speed or high-performance operation of the pump. In addition, the blade clearance leakage of the open impeller is large, resulting in low hydraulic efficiency. In this embodiment, the mechanical pump includes a pump cover 1, an impeller assembly 2, a sealing ring 3, an end cover 4, a housing 5, a stator skeleton 6, a coil winding 7, a stator core 8, a rotor sleeve 9, a rotor 10, a shaft sleeve 11, a driving plate 12, and a rear cover 13. The pump cover 1 is provided with a water inlet 1a and a water outlet 1b, and the internal space serves as a pump chamber. The water inlet 1a and the water outlet 1b are respectively communicated with the pump chamber. The pump cover 1 is made of high-strength aluminum alloy or engineering plastic, and the surface is precision machined to ensure the fitting accuracy with the end cover 4 and the housing 5. A sealing groove is provided on the pump cover 1, and the sealing ring 3 is placed in the sealing groove. The pump cover and the housing are locked by screws to form a compression seal on the sealing ring, ensuring the sealing between the end cover 4 and the pump cover 1 and preventing liquid leakage.

[0044] Please refer to Figure 1 and Figure 2 As shown, in this embodiment, the end cover 4 is located between the pump cover 1 and the housing 5 and is connected to the housing by clearance fit. The end cover is provided with a circumferential hole 4b and a central hole 4a. The central hole 4a is used to connect with the impeller assembly 2, and the circumferential hole 4b is communicated with the pump chamber to form a fluid passage, ensuring that the low-pressure liquid in the pump chamber can enter the inner housing cavity to provide hydraulic pressure for the rotor assembly. The end cover is made of high-strength aluminum alloy, and the surface is precision machined to ensure the fitting accuracy with the pump cover and the housing.

[0045] Please refer to Figure 1 and Figure 2 As shown, in this embodiment, the central area of the housing 5 is recessed to form an inner housing cavity, and the housing and the rear cover 13 enclose to form an outer housing cavity. The inner housing cavity is used to accommodate the rotor assembly, and the outer housing cavity is used to accommodate the stator skeleton 6, the coil winding 7, the stator core 8, and the driving plate 12. The housing 5 is made of engineering plastic and is integrally formed by injection molding to ensure structural strength and lightweight design. In this embodiment, the housing provides support for the rotor assembly and, through the separation of the inner housing cavity and the outer housing cavity, ensures the independence of the electromagnetic field and the fluid.

[0046] Please refer to Figure 1 and Figure 2As shown, in this embodiment, the stator assembly includes a stator skeleton 6, a coil winding 7, and a stator core 8. The stator skeleton 6 is an insulating structure installed at the upper and lower ends of the stator core 8, separating the coil winding 7 and the stator core 8. The coil winding 7 is wound around the stator skeleton 6. The stator skeleton 6 is made of a high-strength insulating material, the coil winding 7 is wound with high-strength enameled wire, and the stator core 8 is stacked by multiple magnetic conductive thin sheet materials. The stator assembly generates an electromagnetic field, which interacts with the magnetic field of the rotor assembly to form a magnetic pulling force, realizing the suspension of the rotor assembly.

[0047] Please refer to Figure 1 、 Figure 3 and Figure 4 As shown, in this embodiment, the rotor assembly includes a rotor sleeve 9, a rotor 10, and a shaft sleeve 11. The rotor sleeve 9 is located outside the rotor 10, and the shaft sleeve 11 is located inside the rotor 10. They are in clearance fit with each other and fixed by glue. In this embodiment, the surface of the rotor 10 is provided with an anti-corrosion coating. The rotor sleeve 9 and the shaft sleeve 11 are made of high-strength engineering plastics or aluminum alloy. The rotor 10 is a magnetic material with multiple permanent magnets embedded inside. The rotor assembly generates a magnetic pulling force under the action of the electromagnetic field and cooperates with the hydraulic pressure to achieve full-degree-of-freedom suspension.

[0048] Please refer to Figure 1 、 Figure 3 and Figure 4 As shown, in this embodiment, the impeller assembly 2 includes blades 2a, a wheel disc 2b, and a wheel shaft 2c. The wheel disc 2b is arranged at one end of the wheel shaft 2c, and the blades 2a are arranged on the wheel disc 2b. The blades 2a, the wheel disc 2b, and the wheel shaft 2c can be an integrally formed structure. A plurality of wheel disc through-holes 2d are arranged on the wheel disc 2b, evenly distributed along the circumferential direction of the wheel disc 2b, ensuring that the liquid can uniformly flow into the surroundings of the rotor assembly through the wheel disc through-holes 2d, forming a stable hydraulic pressure to support the rotor assembly. It can be understood that the structural design of the wheel disc 2b increases the contact area between the blade root and the wheel disc, significantly improving the mechanical strength of the blades, preventing blade deformation and failure caused by high-speed or high-performance operation, enhancing the reliability of the impeller, and the uniform distribution of the wheel disc through-holes 2d ensures that the liquid uniformly flows into the surroundings of the rotor assembly, forming a stable hydraulic pressure and enhancing the suspension performance. In this embodiment, the wheel shaft 2c is a flat structure, including single flat, double flat, or multi-flat, and is fixedly connected to the rotor assembly by interference fit, ensuring the stability and precision of the connection. The interference fit between the wheel shaft 2c and the rotor assembly ensures the synchronous rotation of the impeller assembly and the rotor assembly, avoiding connection loosening caused by axial movement. The design of the flat structure ensures a more stable interference fit between the wheel shaft and the rotor assembly, avoiding connection loosening caused by axial movement, significantly improving the connection stability between the wheel shaft and the rotor assembly, and ensuring the reliability of the mechanical pump during high-speed operation.

[0049] Please refer to Figure 1 、Figure 3 and Figure 4 As shown, in this embodiment, the wheel disc 2b can be set as a semi-closed type, and of course, it can also be set as a fully-closed structure wheel disc 2b', so as to increase the contact area between the blade root and the wheel disc structure, improve the mechanical strength of the blade root, prevent blade deformation and failure caused by high-speed or high-performance operation, and improve the mechanical reliability of the impeller. Further, the outer diameter of the wheel disc 2b can be set to be greater than, less than or equal to the outer diameter of the blade 2a. Specifically, the ratio range of the outer diameter of the wheel disc 2b to the outer diameter of the blade 2a is 0.1-1.5. By optimizing the design, the tip clearance leakage is reduced, and the hydraulic efficiency of the pump is improved. A flow guiding boss is provided at the bottom of the wheel disc 2b, and the flow guiding boss forms a stepped fluid acceleration channel along the direction towards the center position of the wheel disc 2b. The stepped fluid acceleration channel of the flow guiding boss optimizes the fluid flow path, improves the formation efficiency of the liquid pressure, and enhances the suspension performance.

[0050] Please refer to Figure 1 , Figure 5 and Figure 6 As shown, in this embodiment, there are four main fluid channels designed inside the mechanical pump, namely the first fluid channel, the second fluid channel, the third fluid channel and the fourth fluid channel. The path of the first fluid channel is that the liquid flows into the gap between the rotor assembly and the end cover 4 through the through hole 2d of the wheel disc and the circumferential hole 4b on the end cover 4. This channel provides the initial liquid pressure for the rotor assembly to ensure that the rotor assembly can quickly form a suspended state when starting. The number and diameter of the circumferential holes 4b are optimized to ensure that the liquid can flow into the periphery of the rotor assembly evenly and form a stable liquid pressure. The path of the second fluid channel is that the liquid flows downward through the gap between the wheel shaft 2c of the impeller assembly 2 and the inner hole of the rotor assembly. This channel provides the liquid pressure for the bottom of the rotor assembly to ensure the suspension stability of the rotor assembly in the axial direction. The gap between the wheel shaft 2c and the inner hole of the rotor assembly is precisely machined to ensure smooth liquid flow and reduce energy loss. The path of the third fluid channel is the gap in diameter between the rotor assembly and the inner shell cavity. The liquid undergoes centrifugal acceleration in this path. Further, a flow guiding groove is provided at the bottom of the inner shell cavity of the casing 5 to optimize the liquid flow path and improve the formation efficiency of the liquid pressure. The path of the fourth fluid channel is that the liquid flows back to the first fluid channel through the gap between the rotor assembly and the wall surface of the inner shell cavity of the casing 5. This channel forms a circulating flow to ensure that the liquid can continuously provide liquid pressure for the rotor assembly and take away the heat generated during operation at the same time.

[0051] It is understandable that the liquid film in the fourth fluid channel forms a radial support for the rotor assembly, while the axial suspension of the rotor assembly is achieved by the combined action of magnetic pull and fluid axial force. The thickness of the liquid film is optimized through hydrodynamic design to ensure the stability of the rotor assembly during high-speed operation. Further, a spiral return groove is provided between the rotor assembly and the inner wall of the housing 5, and the pitch gradually decreases along the liquid flow direction. The design of the return groove optimizes the fluid flow path, reduces energy loss, and can guide the liquid to form a vortex liquid film, further optimizing the fluid flow path and improving the suspension performance.

[0052] Please refer to Figure 1 , Figure 5 and Figure 6 As shown, in this embodiment, when the mechanical pump operates, the liquid flows into the pump chamber from the water inlet 1a. Most of the liquid flows out to the water outlet 1b after the impeller rotates and does work, and a small part of the liquid flows into the inner housing cavity through the through holes 2d of the wheel disc and the circumferential holes 4b of the end cover 4. The liquid forms a circulating flow through the first fluid channel, the second fluid channel, the third fluid channel, and the fourth fluid channel. The liquid forms a circulating flow through the four fluid channels to provide hydraulic pressure to support the rotor assembly, and the rotor assembly realizes full-degree-of-freedom suspension through the coupling action of hydraulic pressure and electromagnetic force. The overall design of the mechanical pump realizes full-degree-of-freedom suspension, avoids mechanical friction, extends the service life, meets the requirements of high-reliability application scenarios, and the optimized fluid channel design and wheel disc structure significantly improve the hydraulic efficiency of the pump, reduce the operating noise, and ensure the stability and reliability of the mechanical pump during high-speed or high-performance operation.

[0053] When the mechanical pump of the present invention operates at high speed, the mechanical strength of the impeller assembly is significantly improved, and no deformation failure phenomenon occurs at the blade root. The leakage at the tip clearance is reduced, the hydraulic efficiency is increased by about 15%, the rotor assembly realizes full-degree-of-freedom suspension, operates smoothly, has no mechanical friction, the noise is reduced by about 20 decibels, and the service life is extended to more than 10 years, meeting the requirements of high-reliability application scenarios.

[0054] In summary, the present invention proposes a magnetic liquid coupling suspension mechanical pump with a disc impeller and an impeller assembly. Through the structural design of the wheel disc, the contact area between the blade root and the wheel disc is increased, the mechanical strength of the blade is significantly improved, the blade deformation failure caused by high-speed or high-performance operation is prevented, the reliability of the impeller is improved. At the same time, through the optimized design of the ratio of the outer diameter of the wheel disc to the outer diameter of the blade, the leakage at the tip clearance is reduced, the hydraulic efficiency of the pump is improved, which is beneficial to the improvement of hydraulic pressure, enabling the rotor assembly to realize full-degree-of-freedom suspension, avoiding mechanical friction, extending the service life of the mechanical pump, and meeting the requirements of high-reliability application scenarios.

[0055] The above-described embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included within the protection scope of the present invention.

[0056] Except for the technical features described in the specification, the remaining technical features are well-known technologies to those skilled in the art. To highlight the innovative features of the present invention, the remaining technical features will not be described in detail herein.

Claims

1. An impeller assembly for a magnetic fluid coupled suspended mechanical pump, characterized in that: include: blades (2a), wheel discs (2b) and axles (2c), The wheel shaft (1) is used for being fixedly connected to the rotor assembly of the magnetic fluid coupling suspension mechanical pump; The wheel disc (2b) is arranged at one end of the wheel axle (2c); The blades (2a) are arranged on the wheel disc (2b); Wherein, at least one wheel disc through hole (2d) is provided on the wheel disc (2b), and liquid flows into the periphery of the rotor assembly through the wheel disc through hole (2d) to form liquid pressure to support the rotor assembly.

2. The impeller assembly for a magnetic-fluid coupled suspended mechanical pump according to claim 1, characterized in that: The wheel axle (2c) is a flat structure, including a single flat, a double flat or a multi-flat structure, and the flat structure is connected to the rotor assembly through an interference fit.

3. The impeller assembly for a magnetic-fluid coupled suspended mechanical pump according to claim 1, characterized in that: The ratio of the outer diameter of the wheel disc (2b) to the outer diameter of the blade (2a) is in the range of 0.1 to 1.

5.

4. The impeller assembly for a magnetic-fluid coupled suspended mechanical pump according to claim 1, characterized in that: The wheel disc through holes (2d) are multiple in number and are evenly distributed along the circumference of the wheel disc (2b).

5. The impeller assembly for a magnetic-fluid coupled suspended mechanical pump according to claim 1, characterized in that: The wheel disc (2b) is of a semi-enclosed or fully-enclosed structure.

6. The impeller assembly for a magnetic-fluid coupled suspended mechanical pump according to claim 1, characterized in that: A flow-guiding boss is provided at the bottom of the wheel disc (2b), and the flow-guiding boss forms a stepped fluid acceleration channel in a direction toward the center of the wheel disc (2b).

7. A magnetic fluid coupling suspension mechanical pump with a disc impeller, characterized in that: include: A pump cover (1), an end cover (4), a casing (5), a stator assembly, a rotor assembly and an impeller assembly (2) according to any one of claims 1 to 6; A pump cavity is formed in the pump cover (1); The central area of ​​the housing (5) is concave to form an inner housing cavity; The end cover (4) is located between the pump cover (1) and the casing (5), and a circumferential hole (4b) is provided on the end cover (4); The wheel disc through hole (2d) of the impeller assembly (2) is connected to the circumferential hole (4b) to form a fluid passage from the pump chamber to the inner shell chamber, so that the low-pressure liquid in the pump chamber can enter the cavity wall of the inner shell chamber and the periphery of the rotor assembly through the fluid passage; The rotor assembly realizes full-freedom suspension through the coupling effect of hydraulic pressure and electromagnetic force, wherein the hydraulic pressure is generated by the liquid flowing through the wheel disc through hole (2d), and the electromagnetic force is formed by the interaction of the magnetic fields of the stator assembly and the rotor assembly.

8. The magnetic-fluid coupled suspended mechanical pump with a disc impeller according to claim 7, characterized in that: A plurality of fluid passages are formed around the rotor, including: A first fluid channel, wherein the liquid flows into the gap between the rotor assembly and the end cover (4) through the wheel disc through hole (2d) and the circumferential hole (4b); A second fluid channel, in which the liquid flows downward through the gap between the wheel shaft (2c) and the inner hole of the rotor assembly; A third fluid channel, in which the liquid is in the gap between the rotor assembly and the bottom of the inner shell cavity of the casing (5), and is centrifugally accelerated in the gap; In the fourth fluid channel, the liquid flows back to the first fluid channel through the gap between the rotor assembly and the wall surface of the inner shell cavity of the casing (5).

9. The magnetic-fluid coupled suspended mechanical pump with a disc impeller according to claim 8, characterized in that: The liquid film in the fourth fluid channel forms radial support for the rotor assembly, and the axial suspension of the rotor assembly is achieved by the synergistic effect of the magnetic pulling force and the axial force of the fluid.

10. The magnetic-fluid coupled suspended mechanical pump with a disc impeller according to claim 7, characterized in that: A spiral reflux groove is provided between the rotor assembly and the inner wall of the casing (5), wherein the pitch of the spiral reflux groove gradually decreases along the flow direction of the liquid, and is used to guide the liquid to form a vortex liquid film.

Images