Hydraulic-magnetic coupling suspension micro pump

Abstract

According to the hydraulic-magnetic coupling suspension micro pump, when the micro pump works, liquid flows in from a water inlet pipe opening, one part of the liquid flows out to a water outlet pipe opening after rotating and acting of an impeller, and the other part of the liquid flows into a first fluid channel between a rotor assembly and an end cover through a circumferential hole of the end cover; one part of the fluid flows out through a center hole of the end cover and is converged into a pump cavity inlet, and the other part of the fluid flows downwards through a second fluid channel between a shaft of the impeller assembly and an inner hole of the rotor assembly and is accelerated through the centrifugal effect in a third fluid channel between the rotor assembly and the bottom of an inner shell cavity of the machine shell; and the fluid flows out of a fourth fluid channel between the rotor assembly and the wall surface of the inner shell cavity of the shell and converges into the first fluid channel. By means of the hydraulic-magnetic coupling suspension micro pump, full-freedom-degree suspension of the rotor assembly in the high-speed rotating process can be achieved, and the product effects of long service life, high performance and low noise are achieved.

Description

Technical Field

[0001] This invention relates to the field of mechanical pumps, and in particular to a hydraulic-magnetic coupled suspension micro pump. Background Technology

[0002] With the rapid development of AI servers, new energy sources, and data centers, electronic devices are becoming increasingly integrated, generating more heat per unit area. Traditional air-cooling solutions can no longer meet the demands of these systems, making the development and large-scale application of active liquid cooling solutions inevitable. Micropumps are the core component of liquid cooling systems, and their performance and reliability directly determine the overall system performance and reliability. Furthermore, as an important research direction in microelectromechanical systems (MEMS), micropumps are widely used in chemical transport systems, specialized pumping systems, and medical equipment.

[0003] Miniature pumps used in liquid cooling applications are contact bearing pumps. These pumps experience mechanical friction losses during high-speed rotation, resulting in a typical lifespan of only 2-3 years. This is insufficient for applications requiring high reliability (such as data centers and charging piles where liquid cooling products can have a lifespan of 10-15 years). The key to solving this problem lies in addressing bearing wear; suspended bearing technology is one promising approach.

[0004] To address this issue, researchers have designed various types of suspended micropumps using magnetic or hydraulic levitation principles. Magnetic levitation bearings require sensors to capture the rotor's position in real time and feed back the position signal to an auxiliary coil, generating a balancing force to keep the rotor constantly suspended. This approach has a complex system structure, significant system losses, and severe heat generation, making it unsuitable for liquid cooling applications. Hydraulic levitation technology allows the rotor to achieve full-degree-of-freedom suspension through the hydraulic action of the fluid inside the pump. Patents CN106949069A and CN106762694A disclose a technical solution for achieving a hydraulically suspended pump using a grooved structure, while patents CN106989050A and CN114001036A disclose a technical solution for achieving a hydraulically suspended pump without a grooved structure. The motor solutions used in these patents are all coreless motors, meaning the coil windings have no iron core at the center, forming a cup-shaped structure. The large air gap in the coreless motor structure affects its efficiency. Meanwhile, the hollow cup motor's coil structure has poor heat dissipation performance, resulting in high coil temperatures. Considering the coil's temperature resistance characteristics, the hollow cup motor cannot meet the requirements of higher power applications. Furthermore, the manufacturing of hollow cup motors requires manual wiring, making fully automated production impossible, which affects production efficiency and leads to higher production costs.

[0005] In summary, current hydraulic suspension pump technologies have significant room for improvement in terms of motor efficiency, heat dissipation performance, and production costs, necessitating the development of new micro-pump solutions. Summary of the Invention

[0006] To address the shortcomings of existing hydraulic suspension pump technologies, this invention proposes a hydraulic-magnetic coupled suspension micro pump. This micro pump features a simple structure, high motor efficiency, good heat dissipation, and low production cost. It can also achieve stable suspension operation under varying working conditions and has high reliability.

[0007] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0008] This invention provides a hydraulic-magnetic coupled suspension micro pump, comprising: a pump cover, an impeller assembly, a sealing ring, an end cover, a housing, a stator frame, a coil winding, a stator core, a rotor sleeve, a rotor, a shaft sleeve, a drive plate, and a rear cover;

[0009] The pump cover is provided with an inlet and an outlet, and the internal space of the pump cover serves as a pump chamber. The inlet and outlet are respectively connected to the pump chamber.

[0010] The central area of ​​the housing is recessed to form an inner cavity, and the housing and the rear cover together form an outer cavity. An end cover is provided between the housing and the pump cover. The end cover and the housing are fitted with a clearance fit. A sealing groove is provided on the pump cover. The sealing ring is placed in the sealing groove. The pump cover and the housing are locked together by screws to form a compression seal on the sealing ring.

[0011] The stator frame, the coil winding, and the stator core together constitute the stator assembly. The stator frame is an insulating structure and is installed at the upper and lower ends of the stator core to separate the coil winding and the stator core. The coil winding is wound on the stator frame.

[0012] The rotor sleeve, the rotor, and the shaft sleeve together form a rotor assembly. The rotor sleeve is located on the outside of the rotor, and the shaft sleeve is located on the inside of the rotor. Each pair of the rotor sleeve, the rotor, and the shaft sleeve is fitted with a clearance and fixed with glue.

[0013] The rotor assembly is placed inside the inner shell cavity and is isolated from the stator assembly by the housing of the machine;

[0014] The end cap is provided with a circumferential hole and a central hole that communicate with the pump chamber;

[0015] The impeller assembly consists of blades, an impeller, and a shaft. The impeller assembly and the rotor assembly are press-fitted together with an interference fit. The end cover is located between the impeller assembly and the rotor assembly, and the impeller assembly passes through the central hole of the end cover.

[0016] The drive board is located in the outer cavity between the housing and the rear cover;

[0017] When the micro pump is working, liquid flows in through the inlet pipe. A portion of the liquid flows out to the outlet pipe after the impeller rotates and does work. Another portion flows into the first fluid channel between the rotor assembly and the end cover through the circumferential hole of the end cover. Subsequently, a portion of the fluid flows out through the central hole of the end cover and merges into the pump inlet water flow. The other portion flows downward through the second fluid channel between the shaft of the impeller assembly and the inner hole of the rotor assembly. It is accelerated by centrifugal force in the third fluid channel between the rotor assembly and the bottom of the inner shell cavity of the housing, and then flows out through the fourth fluid channel between the rotor assembly and the inner shell cavity wall of the housing and merges into the first fluid channel.

[0018] In one embodiment of the present invention, the stator core is a magnetically conductive structure, and the stator core comprises a plurality of stacked magnetically conductive thin sheets.

[0019] In one embodiment of the present invention, the rotor is made of magnetic material and the surface of the rotor is provided with an anti-corrosion coating.

[0020] In one embodiment of the present invention, the shaft of the impeller assembly is a flat structure, which includes single flat, double flat, or multiple flat structures.

[0021] In one embodiment of the present invention, the housing is made of engineering plastic and is integrally injection molded.

[0022] In one embodiment of the present invention, the drive board is built into the micro pump, or the drive board adopts a split structure and is placed outside the micro pump, or the drive board is integrated into the circuit board of the application system.

[0023] In one embodiment of the present invention, the liquid film in the fourth fluid channel provides radial support for the rotor assembly to levitate; wherein, when the centerline of the rotor assembly deviates from the centerline of the stator assembly, it is subjected to a magnetic pull in the direction of the centerline of the stator assembly. The magnetic pull and the axial force of the fluid work together to make the rotor assembly levitate axially, thereby forming a levitation with full degrees of freedom.

[0024] As described above, the present invention provides a hydraulic-magnetic coupled suspension micropump, which can achieve the following beneficial effects:

[0025] 1. Smaller air gap and higher air gap magnetic flux density result in higher efficiency of the motor design, which in turn makes the micro pump more efficient.

[0026] 2. The coil winding is wound around the stator frame and stator core, resulting in better heat dissipation performance and supporting higher power micro pump applications.

[0027] 3. The coil winding can be automatically wound using a winding machine, eliminating the need for manual winding, which greatly improves motor production efficiency and reduces production costs.

[0028] 4. The waterproof sleeve and motor housing are manufactured as a single piece, eliminating the need for assembling the housing and waterproof sleeve together as in existing solutions, thus improving production and assembly efficiency and reducing costs.

[0029] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0030] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of a hydraulic-magnetic coupled suspension micro pump according to one embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the end cap in one embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of the shaft of the impeller assembly in one embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of the inner cavity of the housing in one embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram of the axial force on the rotor in one embodiment of the present invention.

[0036] In the diagram: 1. Pump cover; 1a. Inlet pipe; 1b. Outlet pipe; 2. Impeller assembly; 2a. Blade; 2b. Impeller; 2c. Shaft; 3. Sealing ring; 4. End cover; 4a. Center hole; 4b. Circumferential hole; 5. Housing; 6. Stator frame; 7. Coil winding; 8. Stator core; 9. Rotor sleeve; 10. Rotor; 11. Shaft sleeve; 12. Drive plate; 13. Rear cover; 14. First fluid channel; 15. Second fluid channel; 16. Third fluid channel; 17. Fourth fluid channel. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] refer to Figure 1 , Figure 2 and Figure 3 The present invention discloses a hydraulic-magnetic coupled suspension micro pump, which includes: pump cover 1, impeller assembly 2, sealing ring 3, end cover 4, housing 5, stator frame 6, coil winding 7, stator core 8, rotor sleeve 9, rotor 10, shaft sleeve 11, drive plate 12, and rear cover 13.

[0039] refer to Figure 1 In one embodiment, the pump cover 1 is provided with an inlet 1a and an outlet 1b. The internal space of the pump cover 1 serves as the pump chamber, and the inlet 1a and outlet 1b are respectively connected to the pump chamber. The central area of ​​the housing 5 is recessed to form an inner shell cavity. The housing and the rear cover 13 together form an outer shell cavity. An end cover 4 is provided between the housing 5 and the pump cover 1, and the end cover 4 and the housing 5 are fitted with a clearance fit. The pump cover 1 is provided with a sealing groove, and the sealing ring 3 is placed in the sealing groove. The pump cover 1 and the housing 5 are locked together with screws to form a compression seal for the sealing ring 3. In the liquid entering the micro pump, most of the liquid flows out to the outlet after the impeller rotates and does work, and a small portion of the liquid flows into the inner shell cavity through the circumferential hole of the end cover. In practical applications, the pump chamber and the inner shell cavity are filled with the operating liquid working medium.

[0040] refer to Figure 1 In one embodiment, the stator frame 6, the coil winding 7, and the stator core 8 together constitute a stator assembly. The stator frame 6 is an insulating structure, installed at both ends of the stator core, separating the coil winding 7 from the stator core 8. The coil winding 7 is wound around the stator frame 6.

[0041] refer to Figure 1 In one embodiment, rotor sleeve 9, rotor 10, and shaft sleeve 11 together constitute a rotor assembly. Rotor sleeve 9 is located outside rotor 10, and shaft sleeve 11 is located inside rotor 10. Rotor sleeve 9, rotor 10, and shaft sleeve 11 are fitted together with clearance fits and fixed with adhesive. The surface of rotor 10 is provided with an anti-corrosion coating. The rotor assembly is placed within the inner housing cavity and is isolated from the stator assembly by the housing 5.

[0042] refer to Figure 1 , Figure 2In one embodiment, the end cap 4 is provided with a circumferential hole 4b and a central hole 4a communicating with the pump chamber. The circumferential hole 4b and the central hole 4a connect the liquid passage in the pump chamber and the inner shell chamber.

[0043] refer to Figure 1 , Figure 3 In one embodiment, the impeller assembly 2 consists of blades 2a, an impeller 2b, and a shaft 2c. The impeller assembly and the rotor assembly are press-fitted together with an interference fit, and the interference fit stroke can be precisely controlled by an electronic press or a servo press. The end cover 4 is located between the impeller assembly 2 and the rotor assembly, and the impeller assembly 2 passes through the central hole 4a of the end cover 4.

[0044] refer to Figure 1 , Figure 3 In one embodiment, the shaft 2c of the impeller assembly 2 has a flat structure. The flat structure includes single flat, double flat, or multiple flat structures.

[0045] refer to Figure 1 In one embodiment, the end cap 4 is zero-fitted to the inner wall of the housing 5 and clearance-fitted to the groove on the upper surface of the housing 5. The upper surface of the end cap 4 is pressed and limited by the pump cover 1.

[0046] refer to Figure 1 In one embodiment, the drive board 12 is located in the outer cavity between the housing 5 and the rear cover 13. Corresponding pads on the drive board 12 are soldered to the leads of the coil winding 7 and connected to the terminals of the micropump. In practical applications, depending on the system's power requirements, the drive board 12 can be optionally integrated inside the micropump structure, placed outside the micropump in a separate structure, or integrated into the circuit board of the application system.

[0047] refer to Figure 4 In one embodiment, when the micro pump is operating, liquid flows in through the inlet port 1a. Most of the liquid in the inlet port 1a flows out to the outlet port 1b after the impeller 2b rotates and does work. A portion of the liquid in the inlet port 1a flows into the first fluid channel 14 between the rotor assembly and the end cover 4 through the circumferential hole 4b of the end cover 4. Subsequently, a portion of the fluid in the first fluid channel 14 flows out through the central hole 4a of the end cover 4 and merges into the pump inlet water flow. Another portion of the fluid in the first fluid channel 14 flows downward through the second fluid channel 15 between the shaft 2c of the impeller assembly 2 and the inner hole of the rotor assembly, is accelerated by centrifugal force in the third fluid channel 16 between the rotor assembly and the bottom of the inner cavity of the housing 5, and then flows out through the fourth fluid channel 17 between the rotor assembly and the inner cavity wall of the housing 5 and merges into the first fluid channel 14.

[0048] refer to Figure 5In one embodiment, the suspension principle of the suspended micropump of this application is as follows: the full-degree-of-freedom suspension of the rotor 10 is divided into radial suspension and axial suspension. Regarding radial suspension, the flowing liquid film in the fourth fluid channel 17 is a wedge-shaped liquid film, which can form a hydrodynamic support force to achieve radial suspension of the rotor 10. Regarding axial suspension, the flowing liquid film in the first fluid channel 14 forms a downward axial support fluid force on the rotor 10, and the flowing liquid film in the third fluid channel 16 forms an upward axial support fluid force on the rotor 10. Furthermore, when the centerline of the rotor assembly deviates from the centerline of the stator assembly, the rotor 10 will be subjected to a magnetic force in the direction of the stator assembly centerline. This force, in conjunction with the axial support fluid force, achieves axial suspension of the rotor 10, thereby achieving full-degree-of-freedom suspension and achieving high-speed operation without wear.

[0049] As can be seen, in the above solutions, the suspended micropump of this application has a smaller air gap and a higher air gap magnetic flux density, resulting in higher efficiency of the motor and thus a higher efficiency of the micropump. By winding the coil around the stator frame and stator core, heat dissipation is improved, supporting higher power micropump applications. The coil winding can be automatically manufactured using a winding machine, eliminating the need for manual winding, greatly improving motor production efficiency and reducing production costs. By integrating the waterproof sleeve and motor housing into a single molding process, the assembly process of combining the housing and waterproof sleeve in existing solutions is eliminated, improving production assembly efficiency and reducing costs. This suspended micropump can achieve full-degree-of-freedom suspension of the rotor assembly during high-speed rotation, achieving a long lifespan, high performance, and low noise product effect.

[0050] The embodiments of the present invention disclosed above are merely illustrative of the invention. The embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A hydraulic-magnetic coupled suspended micro pump, characterized in that, include: Pump cover (1), impeller assembly (2), sealing ring (3), end cover (4), housing (5), stator frame (6), coil winding (7), stator core (8), rotor sleeve (9), rotor (10), shaft sleeve (11), drive plate (12), rear cover (13); The pump cover (1) is provided with an inlet (1a) and an outlet (1b), and the internal space of the pump cover (1) serves as a pump chamber. The inlet (1a) and the outlet (1b) are respectively connected to the pump chamber. The central area of ​​the housing (5) is recessed to form an inner cavity. The housing (5) and the rear cover (13) together form an outer cavity. An end cover (4) is provided between the housing (5) and the pump cover (1). The end cover (4) and the housing (5) are fitted with a clearance. A sealing groove is provided on the pump cover (1). The sealing ring (3) is placed in the sealing groove. The pump cover (1) and the housing (5) are locked together by screws to form a compression seal on the sealing ring (3). The stator frame (6), the coil winding (7), and the stator core (8) together form a stator assembly. The stator frame (6) is an insulating structure and is installed at the upper and lower ends of the stator core (8) to separate the coil winding (7) and the stator core (8). The coil winding (7) is wound on the stator frame (6). The rotor sleeve (9), the rotor (10), and the bushing (11) together form a rotor assembly. The rotor sleeve (9) is located outside the rotor (10), and the bushing (11) is located inside the rotor (10). The rotor sleeve (9), the rotor (10), and the bushing (11) are respectively fitted with clearance and fixed with glue. The rotor assembly is placed inside the inner shell cavity and is isolated from the stator assembly by the housing (5); The end cap (4) is provided with a circumferential hole (4b) and a central hole (4a) communicating with the pump chamber; The impeller assembly (2) consists of blades (2a), an impeller (2b) and a shaft (2c). The impeller assembly (2) and the rotor assembly are press-fitted together with an interference fit. The end cover (4) is located between the impeller assembly (2) and the rotor assembly, and the impeller assembly (2) passes through the center hole (4a) of the end cover (4). The drive plate (12) is located in the outer shell cavity between the housing (5) and the rear cover (13); When the micro pump is working, liquid flows in through the inlet (1a), part of the liquid flows out to the outlet (1b) after the impeller (2b) rotates and does work, and part of the liquid flows into the first fluid channel (14) between the rotor assembly and the end cover (4) through the circumferential hole (4b) of the end cover (4). Then, part of the fluid flows out through the central hole (4a) of the end cover (4) and merges into the pump cavity inlet water flow, and another part flows downward through the second fluid channel (15) between the shaft (2c) of the impeller assembly (2) and the inner hole of the rotor assembly. It is accelerated by centrifugal force in the third fluid channel (16) between the rotor assembly and the bottom of the inner shell cavity of the housing (5), and then flows out through the fourth fluid channel (17) between the rotor assembly and the inner shell cavity wall of the housing (5) and merges into the first fluid channel (14).

2. The hydraulic-magnetic coupled suspension micropump according to claim 1, characterized in that, The stator core (8) is a magnetically conductive structure, and the stator core (8) includes multiple stacked magnetically conductive sheet materials.

3. The hydraulic-magnetic coupled suspended micropump according to claim 1, characterized in that, The rotor (10) is made of magnetic material and has an anti-corrosion coating on its surface.

4. The hydraulic-magnetic coupled suspension micropump according to claim 1, characterized in that, The shaft (2c) of the impeller assembly (2) has a flat structure, which includes single flat, double flat or multiple flat structures.

5. The hydraulic-magnetic coupled suspension micropump according to claim 1, characterized in that, The housing (5) is made of engineering plastic and is integrally molded by injection molding.

6. The hydraulic-magnetic coupled suspended micropump according to claim 1, characterized in that, The drive board (12) is built into the micro pump, or the drive board (12) is placed outside the micro pump in a split structure, or the drive board (12) is integrated into the circuit board of the application system.

7. The hydraulic-magnetic coupled suspension micropump according to claim 1, characterized in that, The liquid film in the fourth fluid channel (17) provides radial support for the rotor assembly to levitate. When the centerline of the rotor assembly deviates from the centerline of the stator assembly, it will be subjected to a magnetic pull in the direction of the centerline of the stator assembly. The magnetic pull and the axial force of the fluid work together to make the rotor assembly levitate in the axial direction, thereby forming a levitation with full degrees of freedom.

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