WO2021143526A1

WO2021143526A1 - Mini-type pump

Info

Publication number: WO2021143526A1
Application number: PCT/CN2020/141181
Authority: WO
Inventors: 陈奇; 傅登初; 张治国; 罗小兵; 吴睿康; 范义文
Original assignee: 华为技术有限公司; 华中科技大学
Priority date: 2020-01-13
Filing date: 2020-12-30
Publication date: 2021-07-22
Also published as: CN113187730A; CN113187730B

Abstract

A mini-type pump, comprising a casing body (1), a rotor system (2), and a stator system (3), the casing body (1) having a stator cavity (122) and a rotor cavity that are not in communication, the stator system (3) being arranged inside the stator cavity (122), the rotor system (2) being arranged inside the rotor cavity, and the rotor system (2) rotating relative to the stator system (3); the rotor system (2) has a rotor component (21) and a bearing component (22), the bearing component (22) is installed within the rotor cavity, and the rotor component (21) is installed on the bearing component (22) and rotates with the bearing component (22); the bearing component (22) has a bearing (221) and a bearing shaft (222), the bearing shaft (222) is fixed to the bottom of the rotor cavity, and the bearing (221) is sleeved on the bearing shaft (222), a gap being present between the bearing (221) and the bearing shaft (222); the bottom face of the bearing (221) is oriented toward the bottom of the rotor cavity, and a plurality of recessed grooves (2211) extending from the outer circumference of the bottom face toward the inner circumference of the bottom face are provided on said bottom face, a plurality of the recessed grooves (2211) being distributed around the bearing shaft (222), the openings of the recessed grooves (2211) being connected to the outer circumference of the bottom face and in communication with the rotor cavity, and gaps (2212) being present between the bottoms of the recessed grooves (2211) and the inner circumference of the bottom face.

Description

Micro pump

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office with the application number CN202010032260.2 and the application name "micropump" on January 13, 2020, the entire content of which is incorporated into this application by reference.

Technical field

This application relates to the technical field of micro pumps, and in particular to a micro pump.

Background technique

With the continuous development of various devices in the direction of miniaturization and integration, as the core functional device that drives fluid flow, the demand for miniaturization of pumps is increasingly urgent. Take the electronic device heat dissipation system as an example. The performance of portable electronic devices such as notebook computers and tablet computers continues to increase, and the heat generation is increasing, while the thickness of the products is getting smaller and smaller, and they are facing severe heat dissipation problems. As the next generation of heat dissipation technology, liquid cooling system can provide higher heat dissipation performance than traditional air cooling system. The thickness of its core drive component pump has become a major obstacle to its application in these electronic products.

Micropumps are not only small in size, but also complex in structure and highly integrated, including electrical, fluid, and mechanical components. Because the structure of the micropump is very compact, its bearing system is connected with the liquid cavity, which causes the lubricating oil in the bearing system to be diluted by the working fluid, loss of lubrication ability, direct friction between the shaft and the bearing, and the pump life and noise are greatly deteriorated. Most of the current solutions adopt dynamic sealing, using packing or sealing ring to separate the bearing from the fluid, but this method has poor sealing ability, and the friction between the shaft and the seal will reduce the motor's drive to the impeller output. Force, greatly reduce the performance of the micro pump.

In the ball bearing used in the micro pump in the prior art, a spherical alloy steel ball is installed between the inner steel ring and the outer steel ring, and the middle is filled with grease to reduce the friction in the power transmission process and improve the mechanism by rolling. Transmission efficiency of power. However, the ball bearing has the following disadvantages. First, the grease used in the ball bearing in the long-term operation of the micropump will be easily washed away in water and cause failure; second, due to wear, the life of the ball bearing will be lower; Third, due to wear, it will cause greater noise; fourth, the accuracy of traditional processing and assembly processes is low, which will reduce the overall characteristics of the micropump.

The ceramic bearings used in the micro pumps in the prior art utilize the wear resistance of ceramics to improve the life and reliability of the bearing system. However, the ceramic bearing has the following shortcomings. First, the end face of the ceramic bearing and the lower wear-resistant plate are worn, which will cause greater noise; second, the accuracy of the traditional processing and assembly process is low, which will lead to the overall characteristics of the micropump reduce.

Summary of the invention

The present application provides a micro pump to solve the technical problems of easy wear, short life, high noise, and low precision of bearing components in the micro pump in the prior art.

The present application provides a miniature pump including a housing, a rotor system, and a stator system. The housing has a stator cavity and a rotor cavity that are not connected to each other. The stator system is disposed in the stator cavity, and the rotor system Is arranged in the rotor cavity, the rotor system rotates relative to the stator system; the rotor system has a rotor component and a bearing component, the bearing component is installed in the rotor cavity, and the rotor component is installed in the The bearing component is mounted on and rotates with the bearing component; the bearing component has a bearing and a shaft center, the shaft center is fixed at the bottom of the rotor cavity, the bearing is sleeved on the shaft center, and the There is a gap between the bearing and the shaft center; the bottom surface of the bearing faces the bottom of the rotor cavity, and the bottom surface is provided with a plurality of grooves extending from the outer circumference of the bottom surface to the inner circumference of the bottom surface , A plurality of the grooves are arranged around the shaft center, the notches of the grooves are connected with the outer circumference of the bottom surface and communicate with the rotor cavity, and the groove bottom of the grooves is connected to the inner surface of the bottom surface. There are gaps between weeks. Through the solution provided by this embodiment, the multiple grooves on the bottom surface of the bearing and the gap between the bearing and the shaft center are utilized. When the bearing component works, the working fluid in the rotor cavity flows into the gap and the groove, forming in the gap The stable liquid film creates a hydrodynamic pressure difference between the groove and the bottom of the groove, so that in the axial direction, the bearing can be suspended in the working fluid in the rotor cavity due to the buoyancy of the liquid film, and the rotor system can also be suspended in the working fluid. In the working fluid of the rotor cavity, the bearing parts of the miniature pump are free of wear and noise during operation.

In a possible design, the center line of the notch of the groove and the center line of the groove bottom of the groove both pass through the center of the shaft center and form an angle with each other. Through the solution provided by this embodiment, when the bearing is rotating, the working fluid in the rotor cavity flows into the groove more easily and smoothly, and the collision between the working fluid and the inner wall of the groove is reduced during the flow of the working fluid. The kinetic energy loss.

In a possible design, the grooves are arc-shaped, and the notch of each groove is curved in the same direction in the circumferential direction of the bottom surface of the bearing relative to the bottom of the groove. . Through the solution provided by this embodiment, the working fluid flows more smoothly in the grooves. In each groove, the fluid dynamic pressure applied by the working fluid to the bottom of the groove points to the axis, so that the gap The liquid film is more stable, and the liquid film between the bearing and the shaft is also more stable.

In a possible design, the inner diameter of the notch of the groove is larger than the inner diameter of the groove bottom of the groove. The solution provided by this embodiment makes it easier for the working liquid to flow into the groove through the groove of the groove, and the flow rate of the working liquid at the bottom of the groove is faster than the flow rate at the groove of the groove. A high hydrodynamic pressure difference is formed between the notch of the groove and the bottom of the groove.

In a possible design, the inner diameter of the groove gradually decreases from the notch of the groove to the bottom of the groove. Through the solution provided by this embodiment, the flow rate of the working liquid in the groove is gradually increased from the groove to the bottom of the groove, and the hydraulic dynamic pressure of the working liquid on the groove becomes even larger, which is more conducive to the groove opening and the groove. A stable liquid dynamic pressure difference is formed between the bottoms, and then a stable liquid film is formed in the gap.

In a possible design, the shaft includes a rotating shaft and a gasket, the rotating shaft and the gasket are integrally formed, and the gasket is fixed to the bottom of the rotor cavity and is located at the bottom of the rotor cavity and the gasket. There is a gap between the bottom surface of the bearing, the bottom surface of the bearing and the gasket, and a gap is provided between the inner wall of the bearing and the outer wall of the shaft center. Through the solution provided by this embodiment, the shim is used to reinforce the rotating shaft from the radial direction to limit the vibration of the rotating shaft in the radial direction during rotation, and the shim protects the bottom of the rotor cavity from working in the axial direction. The erosion and abrasion of the liquid increase the service life of the micro pump.

In a possible design, a bearing hole is provided at the center of the bottom of the rotor cavity, and the rotating shaft is fixed in the bearing hole. With the solution provided by this embodiment, the rotating shaft is reinforced in both the axial direction and the radial direction, and the vibration and displacement of the rotating shaft in both directions are restricted.

In a possible design, the rotor component includes an impeller and a permanent magnet, the impeller has a wheel face and a hub, the wheel face is sleeved on the outer wall of the bearing, and the hub is located between the wheel face and the hub. Between the bottom of the rotor cavity, the permanent magnet is installed on the inner ring of the hub close to the axis; the stator system includes a motor stator and a stator winding, the motor stator is fixed in the stator cavity, so The stator winding surrounds the motor stator and is arranged on the side wall of the stator cavity; the permanent magnet surrounds the periphery of the stator winding. Through the solution provided by this embodiment, the stator and stator windings of the motor generate an alternating magnetic field. The permanent magnet drives the impeller to rotate under the action of the alternating magnetic field. The rotation of the impeller does work on the working fluid and drives the working fluid to flow, so that the rotor system is in diameter. It can be suspended in the working fluid in the direction to achieve the technical effect of no wear and no noise.

In a possible design, the axial position of the permanent magnet is different from the axial position of the stator system. With the solution provided by this embodiment, the rotor system is subjected to a magnetic force directed to the stator system in the axial direction. In this way, the rotor system can be suspended in the rotor cavity in the axial direction to achieve the technical effect of no wear and noise.

In a possible design, the inner ring of the hub is provided with an annular groove, and a motor shell is fixed in the annular groove, and the motor shell is located between the inner ring of the hub and the permanent magnet. Through the solution provided by this embodiment, the rigidity of the motor housing is used to increase the rigidity of the hub of the impeller.

In a possible design, the impeller, the motor housing and the bearing are integrally formed. Through the solution provided by this embodiment, the assembly accuracy of the rotor component and the bearing is ensured.

In a possible design, the housing includes a volute and a base, and the volute and the base are connected and fixed together by a fixing component; the volute has a volute cavity, and the base has a base cavity and the base. A stator cavity, the volute cavity communicates with the base cavity to form the rotor cavity, the bearing component is fixed at the bottom of the base cavity, and the base cavity surrounds the stator cavity. Through the solution provided by this embodiment, the housing is designed into two detachable parts, which is convenient for users to maintain, clean, and assemble and disassemble the inside of the housing.

In a possible design, the surface of the volute facing the base is further provided with a sealing groove not communicating with the cavity of the volute, and a sealing element is provided in the sealing groove. Through the solution provided by this embodiment, the leakage of the working fluid can be effectively prevented.

In a possible design, the shaft center has a rotating shaft and a spacer, the rotating shaft and the spacer are integrally formed, and the rotating shaft, the spacer and the base are integrally formed. The solution provided by this embodiment can ensure the assembly accuracy of the shaft and the base.

It can be seen that, in the above aspects, by arranging spirally arranged grooves on the bearing, and arranging a gasket parallel to the bottom surface of the bearing at the gap between the bottom surface of the bearing and the bottom of the rotor cavity, the groove can be The bottom of the groove generates a higher hydrodynamic pressure, which makes the liquid film formed between the bearing and the gasket in the axial direction more stable, and forms a more stable liquid film in the gap between the shaft and the shaft in the radial direction. ; By designing the axial position of the stator system and the axial position of the permanent magnets at different positions, as well as bearing parts with hydraulic support, the rotor system is suspended in the working fluid in both the axial and radial directions, without wear And noise; by adopting the structure and process of integral molding of impeller and bearing, and integral molding of base and axis, the assembly accuracy of the micro pump can be effectively improved to ensure the hydraulic performance of the micro pump and lower vibration and noise.

Description of the drawings

FIG. 1 is an exploded view of a micro pump provided in Embodiment 1 of the application;

2 is a cross-sectional view of a micro pump provided in Embodiment 1 of the application;

FIG. 3 is a perspective view of a rotor component in a miniature pump provided in Embodiment 1 of the application; FIG.

4 is a perspective view and a partially enlarged cross-sectional view of a bearing component in a miniature pump provided by Embodiment 1 of the application;

FIG. 5 is a perspective view of a bearing in a miniature pump provided in Embodiment 1 of the application; FIG.

FIG. 6 is a schematic diagram of the force of the rotor system in a micro pump provided in Embodiment 1 of the application.

Reference signs:

1-shell;

11-Volute;

111-volute cavity;

112-seal groove;

113-seal;

12-Base;

121- Base cavity;

122-stator cavity;

123-controller slot;

124-bearing hole;

125-import pipe;

126-Exit pipe;

2-rotor system;

21- Rotor parts;

211-impeller;

2111-wheel noodles;

2112-wheel hub;

2113-Annular groove;

212-Permanent magnet;

213-Motor housing;

22-Bearing parts;

221-bearing;

2211-groove;

2212-interval;

222-axis;

2221-Rotating shaft;

2222-gasket;

3-stator system;

31-Motor stator;

32-stator winding;

4- Controller;

5-Fixed components.

Detailed ways

In order to better understand the technical solutions of the present application, the following describes the embodiments of the present application in detail with reference to the accompanying drawings.

It should be clear that the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of this application.

The terms used in the implementation mode part of this application are only used to explain specific embodiments of this application, and are not intended to limit this application. The singular forms of "a", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

It should be noted that the “upper”, “lower”, “left”, “right” and other directional words described in the embodiments of the present application are described from the angle shown in the drawings, and should not be construed as implementing the present application. Limitations of examples. In addition, in the context, it should also be understood that when it is mentioned that an element is connected "on" or "under" another element, it can not only be directly connected "on" or "under" the other element, but also It is indirectly connected "on" or "under" another element through an intermediate element.

Please refer to attached drawings 1-6, in which Figure 1 is an exploded view of a micro pump provided in Example 1 of this application; Figure 2 is a cross-sectional view of a micro pump provided in Example 1 of this application; Application Example 1 provides a three-dimensional view of the rotor component in a micro pump; Figure 4 is a perspective view and a partial enlarged cross-sectional view of a bearing component in a micro pump provided in Example 1 of the application; Figure 5 is an embodiment of the application 1 provides a perspective view of a bearing in a micro pump; FIG. 6 is a schematic diagram of a force on a rotor system in a micro pump provided in Example 1 of the application.

As shown in Figures 1 and 2, the embodiment of the present application provides a micro pump, which has magnetic and hydraulic support, so that it will not produce mechanical friction during work, and has a simple structure, which greatly improves performance, service life, and Vibration and noise generated during work.

The micro pump of this embodiment includes a housing 1, a rotor system 2 and a stator system 3.

Wherein, the housing 1 has a stator cavity 122 and a rotor cavity that are not connected to each other. The stator system 3 is arranged in the stator cavity 122, the rotor system 2 is arranged in the rotor cavity, and the rotor system 2 rotates relative to the stator system 3, in the rotor cavity Filled with working fluid.

Specifically, in the micro pump of this embodiment, the housing 1 is designed as two detachable parts, including a volute 11 and a base 12, and the volute 11 and the base 12 are connected and fixed together by a fixing assembly 5. The housing 1 is designed as two detachable parts, so that the user can maintain, clean, and assemble and disassemble the interior of the housing 1 easily. The volute 11 has a volute cavity 111, and the base 12 has a base cavity 121 and a stator cavity 122. The volute cavity 111 communicates with the base cavity 121 to form a rotor cavity, which provides space for the rotor system 2 and the working fluid. The base cavity 121 surrounds the stator The cavity 122, the stator cavity 122 is an annular structure located inside the base cavity 121 and separated from the base cavity 121. An inlet pipe 125 and an outlet pipe 126 are also provided on the base cavity 121, and the inlet pipe 125 and the outlet pipe 126 are used to provide passages for the working fluid to enter and exit the micro pump. The surface of the volute 11 facing the base 12 is further provided with a sealing groove 112 that is not connected to the volute cavity 111, and a sealing member 113 is provided in the sealing groove 112. Since the rotor system 2 rotates at a high speed in the rotor cavity formed by the volute cavity 111 and the base cavity 121, it will drive the working fluid to make centrifugal movement. The sealing groove 112 and the seal 113 can effectively prevent the working fluid from being thrown out of the rotor cavity due to centrifugal movement. And leaked.

As shown in Figures 3-6, the rotor system 2 has a rotor component 21 and a bearing component 22. The bearing component 22 is installed in the rotor cavity and fixed to the bottom of the base cavity 121, and is located at the center of the inner side of the stator cavity 122. The component 21 is mounted on the bearing component 22 and rotates with the bearing component 22. Specifically, the bearing component 22 has a bearing 221 and a shaft 222, the shaft 222 is fixed at the bottom of the rotor cavity, the bearing 221 is sleeved on the shaft 222, there is a gap between the bearing 221 and the shaft 222, the bearing 221 and the shaft The core 222 is made of ceramic material; the bottom surface of the bearing 221 faces the bottom of the rotor cavity, and the bottom surface is provided with a plurality of grooves 2211 extending from the outer circumference of the bottom surface to the inner circumference of the bottom surface, and the plurality of grooves 2211 are arranged around the shaft core 222 The notch of the groove 2211 is connected to the outer circumference of the bottom surface and communicates with the rotor cavity, and there is an interval 2212 between the groove bottom of the groove 2211 and the inner circumference of the bottom surface. A plurality of grooves 2211 are provided on the bottom surface of the bearing 221. The plurality of grooves 2211 do not penetrate the inner circumference of the bottom surface and form a spiral shape. The plurality of spiral grooves 2211 are equally spaced along the circumferential direction of the bottom surface of the bearing 221. The arrangement is rotationally symmetrical about the axis 222. When the micropump is working, the bearing 221 rotates with the rotor system 2, and the working fluid enters from the slot of the groove 2211, enters the bottom of the groove 2211 along the extending direction of the groove 2211, and is blocked by the inner wall of the groove 2211. A higher hydrodynamic pressure is generated, thereby generating a low pressure area at the notch of the groove 2211, and a high pressure area at the bottom of the groove 2211, so that the working fluid has a hydraulic pressure outward from the shaft 222 to the bearing 221 The thrust force is used to form a more stable liquid film at the gap between the bearing 221 and the shaft 222, so that the bearing 221 can be suspended in the working fluid in the radial direction, and there is no mechanical friction between the bearing 221 and the shaft 222. The shaft 222 has a shaft 2221 and a gasket 2222. The shaft 2221 and the gasket 2222 are integrally formed. The shaft 2221 and the gasket 2222 are integrally formed with the base 12 to ensure the assembly accuracy of the shaft 222 and the base 12.

In the micro pump of this embodiment, a plurality of spiral grooves 2211 are formed on the bottom surface of the bearing 221 and the gap between the bearing 221 and the shaft 222. When the bearing component 22 is working, the working fluid in the rotor cavity flows into the gap and The groove 2211 forms a stable liquid film in the gap, and a fluid dynamic pressure difference is formed between the notch and the bottom of the groove 2211, so that in the axial direction, the bearing 221 can be suspended in the rotor cavity due to the buoyancy of the liquid film. In the liquid, the rotor system 2 can also be suspended in the working liquid in the rotor cavity, so that the bearing component 22 of the micropump is free from wear and noise during operation.

In the micro pump of this embodiment, the center line of the notch of the groove 2211 and the center line of the groove bottom of the groove 2211 both pass through the center of the shaft 222 and are at an angle to each other. Specifically, the bottom surface of the bearing 221 is in the shape of a ring with an inner periphery and an outer periphery, and a plurality of radial lines extend outward from the shaft center 222, and are arranged in a plurality of grooves 2211 on the bottom surface of the bearing 221, each The center line of the notch of the groove 2211 and the center line of the groove bottom of the groove 2211 are respectively on the same straight line with different radial lines, that is, they are at an angle to each other. When the bearing 221 is rotating, the working fluid in the rotor cavity flows into the groove 2211 more easily and smoothly, and the kinetic energy loss caused by the collision between the working fluid and the inner wall of the groove 2211 is reduced during the flow of the working fluid.

Further, the groove 2211 is arc-shaped, and the notch of each groove 2211 is curved in the same direction in the circumferential direction of the bottom surface of the bearing 221 relative to the groove bottom of the groove 2211. When the bending direction of the groove 2211 is the same as the rotation direction of the rotor system 2, when the rotor system 2 rotates, the working fluid flows into the groove 2211, exerting dynamic pressure on the inner wall and the groove bottom of the groove 2211. When the bending direction of the groove 2211 is opposite to the rotation direction of the rotor system 2, when the rotor system 2 rotates, the working fluid is sucked into the groove 2211, and dynamic pressure is also applied to the inner wall and the groove bottom of the groove 2211. Due to the arc shape of the groove 2211, the working fluid flows more smoothly in the groove 2211. In each groove 2211, the fluid dynamic pressure applied by the working fluid to the bottom of the groove 2211 is directed to the axis 222. , So that the liquid film at the gap is more stable, and the liquid film between the bearing 221 and the shaft 222 is also more stable.

Further, the inner diameter of the notch of the groove 2211 is greater than the inner diameter of the groove bottom of the groove 2211, that is, the radius of curvature of the inner arc surface of the groove 2211 is smaller than the radius of curvature of the outer arc surface. During the rotation of the rotor system 2, the working fluid is more likely to flow into the groove 2211 through the notch of the groove 2211, and the flow velocity of the working fluid at the bottom of the groove 2211 is faster than the flow velocity at the notch of the groove 2211. It is easier to form a higher hydrodynamic pressure difference between the notch of the groove 2211 and the bottom of the groove.

Further, the inner diameter of the groove 2211 gradually decreases from the notch of the groove 2211 to the bottom of the groove 2211. Specifically, along the radial direction passing through the center line of the shaft core 222, the closer to the inner circumference of the bottom surface of the bearing 221, the smaller the inner diameter of the groove 2211, so that the flow rate of the working fluid in the groove 2211 changes from the groove 2211. Gradually speed up from the mouth to the bottom of the groove, and the working fluid will uniformly increase the hydrodynamic pressure of the groove 2211, which is more conducive to the formation of a stable hydrodynamic pressure difference between the groove 2211 and the groove bottom, thereby forming a stable gap at the gap.的液膜。 The liquid film.

Further, the shaft 222 includes a rotating shaft 2221 and a gasket 2222. The rotating shaft 2221 and the gasket 2222 are integrally formed. The gasket 2222 is fixed to the bottom of the rotor cavity and located between the bottom of the rotor cavity and the bottom surface of the bearing 221. The bottom surface of the bearing 221 There is a gap between the spacer 2222 and the inner wall of the bearing 221 and the outer wall of the shaft 222. Specifically, in the micro pump of this embodiment, the shaft 222 has two parts, one is a shaft 2221 that passes through the center of the bearing 221 and is fixed at the bottom of the rotor cavity, and the other is sleeved outside the shaft 2221 and integrated with it. The gasket 2222 formed between the bottom surface of the bearing 221 and the bottom of the rotor cavity forms a liquid film at the gap between the bearing 221 and the gasket 2222, the bearing 221 and the shaft 2221 when the rotor system 2 rotates, so that The bearing 221 can be completely suspended in the working fluid without mechanical friction and noise. At the same time, the gasket 2222 can also reinforce the shaft 2221 in the radial direction, and limit the vibration of the shaft 2221 in the radial direction during the rotation. At the same time, the gasket 2222 protects the bottom of the rotor cavity from the working fluid in the axial direction. The erosion and abrasion of the micro-pump can improve the service life of the micro-pump.

Furthermore, a bearing hole 124 is provided in the center of the bottom of the rotor cavity, and the rotating shaft 2221 is fixed in the bearing hole 124. Specifically, the bearing hole 124 is recessed in the center of the bottom of the rotor cavity, and the rotating shaft 2221 is embedded and fixed in the bearing hole 124. The bearing hole 124 strengthens the rotating shaft 2221 in both the axial direction and the radial direction, and restricts the rotating shaft 2221. Vibration and displacement in two directions.

As shown in Figures 3 to 6, the rotor component 21 includes an impeller 211 and a permanent magnet 212. The impeller 211 has a wheel face 2111 and a hub 2112. The wheel face 2111 is sleeved on the outer wall of the bearing 221. The hub 2112 is located between the wheel face 2111 and the rotor cavity. The permanent magnet 212 is installed in the inner ring of the hub 2112 close to the axis 222; the stator system 3 includes a motor stator 31 and a stator winding 32. The motor stator 31 and the stator winding 32 are installed in a closed stator cavity 122. The motor stator 31 is fixed in the stator cavity 122, the stator winding 32 surrounds the motor stator 31 and is arranged on the side wall of the stator cavity 122, and the permanent magnet 212 surrounds the periphery of the stator winding 32. The base 12 is provided with a controller slot 123, and the controller 4 is set in the controller slot 123 of the base 12 and connected to the stator system 3. When the controller 4 is powered on, the stator winding 32 introduces current and connects with the motor stator 31 The alternating magnetic field is generated together, and the stator system 3 can effectively achieve electrical insulation because it does not contact the working fluid.

The motor stator 31 and the stator winding 32 generate an alternating magnetic field. Using the magnetic force between the permanent magnet 212 and the stator system 3, the permanent magnet 212 drives the impeller 211 to rotate under the action of the alternating magnetic field, and the impeller 211 rotates to perform work on the working fluid. The working fluid is driven to flow, so that the rotor system 2 can be suspended in the working fluid in the radial direction, and the technical effect of no wear and no noise is achieved.

Further, the axial position of the permanent magnet 212 is different from the axial position of the stator system 3. Specifically, in the axial direction, the horizontal center plane of the permanent magnet 212 and the horizontal center plane of the stator system 3 are not the same plane, and relative to the bottom of the rotor cavity, the position of the permanent magnet 212 is slightly higher than that of the stator system 3. Position, so that the rotor system 2 receives a magnetic force directed to the stator system 3 in the axial direction, so that the rotor system 2 can be suspended in the rotor cavity in the axial direction to achieve the technical effect of no wear and noise.

Further, the inner ring of the hub 2112 is provided with an annular groove 2113, and a motor housing 213 is fixed in the annular groove 2113. The motor housing 213 is located between the inner ring of the hub 2112 and the permanent magnet 212. The rigid motor housing 213 is used to improve the impeller. 211 the hardness of the hub 2112. The impeller 211, the motor housing 213 and the bearing 221 are integrally formed to ensure the assembly accuracy of the rotor component 21 and the bearing 221.

When the micro pump of this embodiment is in use, after the controller 4 is powered on, current is introduced into the stator winding 32 to generate an alternating magnetic field. The permanent magnet 212 drives the impeller 211 to rotate under the action of the alternating magnetic field, and the working fluid is introduced from the inlet. The tube 125 flows into the rotor cavity formed by the base cavity 121 and the volute cavity 111. The rotating impeller 211 does work on the working fluid, which increases the total pressure of the working fluid and flows out from the outlet pipe 126, so that the micropump generates and drives the working fluid to flow. Ability. The bearing 221 rotates with the rotor system 2, and the working fluid enters from the slot of the groove 2211, and enters the bottom of the groove 2211 along the inner wall of the groove 2211, and is blocked by the inner wall of the groove 2211, resulting in higher liquid Dynamic Pressure. Therefore, a low pressure area is generated at the notch of the groove 2211, and a high pressure area is generated at the bottom of the groove 2211, so the working fluid has an outward hydraulic thrust on the bearing 221; at the same time, because the permanent magnet 212 and the stator system 3 The center lines are not in the same position, so the stator system 3 has a magnetic attraction force to the rotor system 2 pointing towards the stator system 3. By adjusting the axial distance between the center lines of the two, the magnetic force can be adjusted. As shown in Fig. 6, the buoyancy, hydraulic pressure, and gravity of the rotor system 2 are analyzed, and a reasonable distance is designed so that the rotor system 2 can be suspended in the liquid under the support of magnetic force and hydraulic pressure, without mechanical friction and noise.

It can be seen that, in the above aspects, by arranging spirally arranged grooves 2211 on the bearing 221, and providing a spacer 2222 parallel to the bottom surface of the bearing 221 at the gap between the bottom surface of the bearing 221 and the bottom of the rotor cavity, It can generate a higher hydrodynamic pressure at the bottom of the groove 2211, so that the liquid film formed between the bearing 221 in the axial direction and the gasket 2222 is more stable. A more stable liquid film is formed at the gap between the two; the axial position of the stator system 3 and the axial position of the permanent magnet 212 are designed at different positions, and the bearing component 22 with hydraulic support makes the rotor system 2 move in the axial direction. It is suspended in the working fluid in the radial direction and has no wear and noise. By adopting the structure and technology that the impeller 211 and the bearing 221 are integrally formed, and the base 12 and the shaft 222 are integrally formed, the assembly accuracy of the micropump can be effectively improved. In order to ensure the hydraulic performance of the micro pump and lower vibration and noise.

The above are only specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention. It should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

A miniature pump includes a housing, a rotor system and a stator system, and is characterized in that:

The housing has a stator cavity and a rotor cavity that are not connected to each other, the stator system is disposed in the stator cavity, the rotor system is disposed in the rotor cavity, and the rotor system rotates relative to the stator system ；

The rotor system has a rotor component and a bearing component, the bearing component is installed in the rotor cavity, and the rotor component is installed on the bearing component and rotates with the bearing component;

The bearing component has a bearing and a shaft center, the shaft center is fixed at the bottom of the rotor cavity, the bearing is sleeved on the shaft center, and there is a gap between the bearing and the shaft center;

The bottom surface of the bearing faces the bottom of the rotor cavity, the bottom surface is provided with a plurality of grooves extending from the outer circumference of the bottom surface to the inner circumference of the bottom surface, and the plurality of grooves surround the shaft The slot of the groove is connected with the outer circumference of the bottom surface and communicates with the rotor cavity, and there is a gap between the groove bottom of the groove and the inner circumference of the bottom surface.
The micro pump according to claim 1, wherein the center line of the notch of the groove and the center line of the bottom of the groove both pass through the center of the shaft center and form an angle with each other.
The micro pump according to claim 2, wherein the groove is arc-shaped, and the notch of each groove is in the circumferential direction of the bottom surface of the bearing relative to the bottom of the groove. Bend up in the same direction.
The micro pump according to any one of claims 1 to 3, wherein the inner diameter of the notch of the groove is larger than the inner diameter of the groove bottom of the groove.
The micro pump according to claim 4, wherein the inner diameter of the groove gradually decreases from the notch of the groove to the bottom of the groove.
The micro pump according to claim 1, wherein the shaft has a rotating shaft and a gasket, the rotating shaft and the gasket are integrally formed, and the gasket is fixed to the bottom of the rotor cavity and is located at the bottom of the rotor cavity. Between the bottom of the rotor cavity and the bottom surface of the bearing, there is a gap between the bottom surface of the bearing and the gasket, and there is a gap between the inner wall of the bearing and the outer wall of the shaft center.
The micro pump according to claim 6, wherein a bearing hole is provided in the center of the bottom of the rotor cavity, and the rotating shaft is fixed in the bearing hole.
The micro pump according to claim 1, wherein the rotor component includes an impeller and a permanent magnet, the impeller has a wheel surface and a hub, the wheel surface is sleeved on the outer wall of the bearing, and the hub is located Between the wheel surface and the bottom of the rotor cavity, the permanent magnet is installed on the inner ring of the hub close to the shaft center;

The stator system includes a motor stator and a stator winding, the motor stator is fixed in the stator cavity, and the stator winding is arranged on a side wall of the stator cavity around the motor stator;

The permanent magnet surrounds the periphery of the stator winding.
8. The micropump according to claim 8, wherein the axial position of the permanent magnet is different from the axial position of the stator system.
The micro pump according to claim 8, wherein the inner ring of the hub is provided with an annular groove, a motor housing is fixed in the annular groove, and the motor housing is located between the inner ring of the hub and the permanent Between magnets.
The micro pump according to claim 8, wherein the impeller, the motor housing and the bearing are integrally formed.
The micro pump according to claim 1, wherein the housing includes a volute and a base, and the volute and the base are connected and fixed together by a fixing component; the volute has a volute cavity, and the base There is a base cavity and the stator cavity, the volute cavity communicates with the base cavity to form the rotor cavity, the bearing component is fixed at the bottom of the base cavity, and the base cavity surrounds the stator cavity.
The micropump according to claim 12, wherein the surface of the volute facing the base is further provided with a sealing groove not communicating with the cavity of the volute, and a sealing element is provided in the sealing groove.
The micro pump according to claim 12, wherein the shaft center has a rotating shaft and a gasket, the rotating shaft and the gasket are integrally formed, and the rotating shaft, the spacer and the base are integrally formed.