CN110701066A

CN110701066A - Vortex type micro pump

Info

Publication number: CN110701066A
Application number: CN201910968988.3A
Authority: CN
Inventors: 罗小兵; 范义文; 吴睿康; 张治国; 陈奇; 傅登初
Original assignee: Huawei Device Co Ltd; Huazhong University of Science and Technology
Current assignee: Huawei Device Co Ltd
Priority date: 2019-10-12
Filing date: 2019-10-12
Publication date: 2020-01-17

Abstract

The invention belongs to the technical field of micro pumps and discloses a vortex type micro pump, which comprises a volute, a rotor assembly, a stator assembly and a base, wherein the volute is connected to the base and forms a pump cavity together; the rotor assembly is accommodated in the pump cavity and is rotationally connected with the base; the stator assembly is arranged in the base, and the rotor assembly is sleeved outside the stator assembly; the rotor assembly comprises a columnar impeller, the impeller is rotationally connected to the base and comprises an impeller base body, a plurality of upper blades, a plurality of lower blades and an annular blade separating body, the blade separating body is arranged on the outer circumference of the impeller base body, the upper blades and the lower blades are respectively arranged on the blade separating body, and the upper blades and the lower blades are respectively positioned on two sides of the blades which are opposite to each other. The invention improves the lift and efficiency, has stronger applicability and compact structure.

Description

Vortex type micro pump

Technical Field

The invention belongs to the technical field of micro pumps, and particularly relates to a vortex micro pump.

Background

The pump is a machine for conveying fluid or pressurizing fluid, and is widely applied to the fields of medicine conveying, aerospace, liquid cooling and heat dissipation of electronic devices and the like. With the development of miniaturization, lightness and thinness of various devices, higher requirements are put on the thickness and volume of a micropump, and the micropump is a complex motion system comprising a plurality of components such as electricity, machinery, fluid and the like, and the thickness and volume of the micropump are difficult to further reduce.

Taking the liquid cooling heat dissipation system of the electronic device as an example, along with the higher and higher integration level and stronger performance of the electronic device, the heat productivity of the electronic device is also higher and higher, if no effective heat dissipation mode exists, the temperature of the electronic device will be higher and higher, the service life and the reliability of the electronic device are seriously threatened, and even the electronic device cannot normally work. The liquid cooling heat dissipation system is widely applied to high-end scenes such as data centers, high-performance personal computers and the like as a new generation of active heat dissipation technology, and can effectively control the temperature of a chip by driving working fluid to take away heat generated by the chip. The micropump is used as a core driving part of the liquid cooling heat dissipation system to drive working fluid to continuously circulate in the liquid cooling system, but the micropump is a bottleneck of miniaturization, lightness and thinness of the liquid cooling heat dissipation system due to the fact that the micropump is complex in structure and comprises moving parts. At present, the size of a micropump with hydraulic performance meeting the requirement of a liquid cooling system on the lift is mostly larger, the requirement of portable electronic equipment (such as a notebook computer, a mobile phone and the like) on the thickness of the micropump cannot be met, and the existing thin micropump is limited in thickness and immature in design method, and mainly has the following problems:

1. the smaller size of the impeller results in a lower head that the micro-pump can provide; 2. the impeller and the pump cavity are designed roughly, and the pump cavity is not matched with the impeller, so that the impeller has more loss on the work of the fluid in the micro pump, and the hydraulic efficiency is low; 3. the motor size is less, and the motor form adopts inner rotor formula more, and rated driving force is not enough, leads to micro-pump during operation, and the motor is in overload state, and efficiency is extremely low.

Disclosure of Invention

In view of the above drawbacks or needs for improvement in the prior art, the present invention provides a vortex micropump, which is based on the working characteristics of the prior micropump and has a high lift and high efficiency. The micropump enables the blades to apply work to the fluid for multiple times through the designed impeller and flow channel structure, so that the impeller with the same size at the same rotating speed has higher lift; and the existence of the blade separating body ensures that the upper fluid and the lower fluid have no impact with each other so as to improve the working efficiency of the impeller on the fluid.

In order to achieve the purpose, the invention provides a vortex type micropump, which comprises a volute, a rotor assembly, a stator assembly and a base, wherein the volute is connected to the base and forms a pump cavity together; the rotor assembly is accommodated in the pump cavity and is rotationally connected with the base; the stator assembly is arranged in the base, and the rotor assembly is sleeved outside the stator assembly;

the rotor assembly comprises a columnar impeller, the impeller is rotationally connected to the base and comprises an impeller base body, a plurality of upper blades, a plurality of lower blades and an annular blade separating body, the blade separating body is arranged on the outer circumference of the impeller base body, the upper blades and the lower blades are respectively arranged on the blade separating body, and the upper blades and the lower blades are respectively positioned on two opposite sides of the blade separating body.

Furthermore, a stepped first pump cavity is formed in the volute, the first pump cavity comprises a first groove and a first arc-shaped groove which are communicated, and the first groove penetrates through the bottom surface of the first arc-shaped groove; the base is provided with a second pump cavity, the second pump cavity and the first pump cavity jointly form the pump cavity, the pump cavity comprises a second groove and a second arc-shaped groove which are communicated, and the second groove penetrates through the bottom surface of the second arc-shaped groove and is annular; the first arc-shaped groove and the second arc-shaped groove form an annular U-shaped groove together, and the upper blade, the lower blade and the blade separating body are contained in the U-shaped groove.

Further, the shape of the U-shaped groove is matched with that of the impeller; the clearance between the upper blade and the inner wall of the U-shaped groove is 0.05 mm-0.2 mm.

Further, the rotor assembly is of a symmetrical structure, and the blade separating bodies are arranged opposite to the connecting parts between the upper blades and the lower blades.

Furthermore, a first drainage groove and a second drainage groove which are arranged at intervals are formed on the volute, and one end of the first drainage groove and one end of the second drainage groove are communicated with the first arc-shaped groove; the volute also comprises a volute bulge, wherein the volute bulge is arranged on the bottom surface of the first arc-shaped groove and is positioned between the first drainage groove and the second drainage groove so as to partition the first drainage groove and the second drainage groove and prevent the direct intercommunication of fluid in the first drainage groove and the second drainage groove.

Furthermore, a third drainage groove and a fourth drainage groove which are arranged at intervals are formed on the base, and one end of the third drainage groove and one end of the fourth drainage groove are respectively communicated with the second arc-shaped groove; the base further comprises a base projection, and the base projection is positioned between the third drainage groove and the fourth drainage groove to isolate the third drainage groove and the fourth drainage groove; the positions and the shapes of the third drainage groove and the fourth drainage groove correspond to those of the first drainage groove and the second drainage groove respectively so as to form two spaced drainage grooves, and the two drainage grooves are used for providing a passage for fluid to enter and exit the U-shaped groove.

Further, the rotor assembly further comprises a motor shell and a permanent magnet, and the annular permanent magnet is arranged in the annular motor shell; the impeller base body is provided with an accommodating groove, the motor shell is arranged in the accommodating groove, and the permanent magnet is sleeved outside the stator assembly.

Further, the rotor assembly further comprises a ceramic shaft and a collar, wherein the collar is arranged at one end of the ceramic shaft; the micropump further comprises a bearing and a wear-resistant sheet, the base is provided with a bearing hole, the bearing is arranged in the bearing hole, one end, provided with the clamping ring, of the ceramic shaft penetrates through the bearing and then extends into the bearing hole, and the wear-resistant sheet is arranged between the ceramic shaft and the bottom surface of the bearing hole; the other end of the ceramic shaft is connected to the impeller.

Furthermore, a stator groove is further formed in one end, far away from the volute, of the base, the stator assembly is arranged in the stator groove, and the central axis of the stator assembly, the central axis of the rotor assembly and the central axis of the ceramic rotating shaft are overlapped.

Further, the micropump further comprises a controller and a sealing member, wherein the controller is connected to the base and is used for controlling the stator assembly; the volute is further provided with a sealing piece groove, the sealing piece is contained in the sealing piece groove and is located between the volute and the base.

Generally, compared with the prior art, the vortex micropump provided by the invention mainly has the following beneficial effects:

1. a blade separating body is arranged between the upper blade and the lower blade, and the upper fluid and the lower fluid of the blade separating body cannot generate impact, so that the internal loss of the fluid is reduced, and the working power of the impeller on the fluid and the efficiency of the micro pump are improved.

2. The upper blade and the lower blade are respectively arranged on the blade separating body, the upper blade and the lower blade are respectively positioned on two opposite sides of the blade separating body, the upper blade and the lower blade rotate to do work on fluid, the fluid leaves the blade area and enters the pump cavity under the action of centrifugal force, the speed of the fluid entering the pump cavity is reduced and the pressure is increased due to the fact that the speed of the fluid in the pump cavity is lower than that of the fluid in the impeller area, the fluid enters the root of the blade under the guiding action of the inner wall, the fluid can enter and exit the pump cavity for multiple times, the fluid can obtain energy from the blades and the pressure is increased when the fluid enters and exits the pump cavity every time, and.

3. The central shaft of the stator component, the central shaft of the rotor component and the central shaft of the ceramic rotating shaft are overlapped, and the rotor component is sleeved outside the stator component, so that a micropump with the same thickness can have a larger motor, and the micropump has the advantages of stronger applicability, compact structure and higher space utilization rate; and an outer rotor type motor type (the rotor assembly is positioned outside the stator assembly) with higher torque is adopted, so that the rated driving force of the motor is improved, the motor works in a high-efficiency area, and the efficiency of the micro pump is further improved.

4. The shape of the U-shaped groove is matched with that of the impeller, and the gap between the upper blade and the inner wall of the U-shaped groove is 0.05-0.2 mm, so that irregular flow of fluid in a pump cavity is reduced, and the working power of the impeller on the fluid is improved.

Drawings

FIG. 1 is an exploded view of a scroll type micro pump according to a preferred embodiment of the present invention;

FIG. 2 is a cross-sectional view of the vortex micro-pump of FIG. 1 taken at an angle;

FIG. 3 is a schematic view of an impeller of the scroll micro-pump of FIG. 1;

FIG. 4 is a schematic view of the volute of the scroll micropump of FIG. 1;

FIG. 5 is a schematic view of the base of the scroll micro-pump of FIG. 1;

FIG. 6 is a schematic view of the volute and base of the scroll micropump of FIG. 1;

FIG. 7 is a partial cross-sectional view of the scroll micro-pump of FIG. 1;

FIG. 8 is a schematic view of the fluid flow of the scroll micro-pump of FIG. 1 in operation;

fig. 9 is a cross-sectional view of the scroll micro-pump of fig. 1 taken at another angle.

The same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein: 1-volute, 101-first pump chamber, 102-volute projection, 103-first drainage groove, 104-second drainage groove, 105-sealing piece groove, 106-threaded hole, 107-positioning hole, 2-sealing piece, 3-rotor assembly, 301-impeller, 3011-impeller base body, 3012-upper blade, 3013-blade separator, 3014-lower blade, 302-motor shell, 303-permanent magnet, 304-ceramic shaft, 305-collar, 4-bearing, 5-wear plate, 6-stator assembly, 601-silicon steel sheet, 602-winding, 7-base, 701-second pump chamber, 702-stator groove, stator-control circuit groove, 704-bearing hole, 705-water outlet 703, 706-water inlet, 707-base projection, 708-third drainage groove, 709-fourth drainage groove, 710-screw hole, 711-positioning column, 8-controller, 9-screw.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Referring to fig. 1, 2 and 9, a scroll micropump according to a preferred embodiment of the present invention includes a scroll casing 1, a sealing member 2, a rotor assembly 3, a bearing 4, a wear plate 5, a stator assembly 6, a base 7, a controller 8 and a plurality of screws 9, wherein the sealing member 2 is disposed in the scroll casing 1 and between the scroll casing 1 and the base 7. The volute 1 is connected to the base 7 by a plurality of screws 9, and the controller 8 is connected to the base 7 and is used for controlling the stator assembly 6. The stator assembly 6 is accommodated in the base 7, and the rotor assembly 3 is rotatably connected to the stator assembly 6. The bearing 4 and the wear-resistant plate 5 are arranged in the base 7.

Referring to fig. 4, 7 and 8, the volute 1 is substantially rectangular and is provided with a stepped first pump cavity 101, the first pump cavity 101 includes a first groove and a first arc-shaped groove, a cross section of the first groove perpendicular to a length direction of the first groove is circular, and a central axis of the first groove coincides with a central axis of the volute 1. The first arc-shaped groove is communicated with the first groove, the first groove penetrates through the bottom surface of the first arc-shaped groove, and the surface of the first arc-shaped groove, facing the rotor assembly 3, is an arc-shaped surface. In this embodiment, the first pump chamber 101 is configured to accommodate the rotor assembly 3.

The volute 1 is further provided with a first drainage groove 103 and a second drainage groove 104, one end of the first drainage groove 103 and one end of the second drainage groove 104 are respectively communicated with the first arc-shaped groove, and the first drainage groove 103 and the second drainage groove 104 are arranged at intervals. The volute 1 further comprises a volute protrusion 102, the volute protrusion 102 is arranged on the bottom surface of the first arc-shaped groove and is located between the first drainage groove 103 and the second drainage groove 104 to isolate the first drainage groove 103 from the second drainage groove 104, and therefore fluid in the first drainage groove 103 and fluid in the second drainage groove 104 are prevented from directly communicating with each other and directly flowing out of the micro pump without passing through the arc-shaped grooves.

The volute casing 1 is further provided with a sealing piece groove 105, and the sealing piece groove 105 is annular and used for accommodating the sealing piece 2. In this embodiment, the center axis of the seal groove 105 coincides with the center axis of the scroll casing 1, and the first drainage groove 103 and the second drainage groove 104 are located in the seal groove 105. The volute 1 is further provided with a plurality of threaded holes 106 and a plurality of positioning holes 107, the threaded holes 106 and the positioning holes 107 are arranged around the sealing piece groove 105, and the threaded holes 106 are used for accommodating the screws 9.

Referring to fig. 3, the rotor assembly 3 is accommodated in a pump cavity formed by the volute 1 and the base 7, and includes an impeller 301, a motor housing 302, a permanent magnet 303, a ceramic shaft 304, and a collar 305, wherein the impeller 301 is stepped, the annular permanent magnet 303 is disposed in the annular motor housing 302, the motor housing 302 is disposed in the impeller 301, the collar 305 is connected to one end of the ceramic shaft 304, and the other end is connected to the impeller 301. The rotor assembly 3 is rotatably connected to the base 7 by the ceramic shaft 304.

The impeller 301 includes a cylindrical impeller base 3011, a plurality of upper blades 3012, an annular blade separator 3013, and a plurality of lower blades 3014, the blade separator 3013 is disposed on an outer circumference of the impeller base 3011, the upper blades 3012 and the lower blades 3014 are disposed on the blade separator 3013, and the upper blades 3012 and the lower blades 3014 are disposed on two opposite sides of the blade separator 3013. The impeller base 3011 is provided with a receiving groove, and a cross section of the receiving groove perpendicular to the length direction of the receiving groove is circular, and the receiving groove is used for receiving the rotor assembly 3. In this embodiment, the impeller base 3011, the upper blades 3012, and the lower blades 3014 are integrally molded.

In this embodiment, the upper blades 3012 and the lower blades 3014 may be uniformly arranged along the circumferential direction of the impeller 301, or may be arranged in a staggered manner, and the number of the upper blades 3012 and the number of the lower blades 3014 are both 20 to 40; the impeller 301 has a symmetrical structure, and the central axis of the impeller 301, the central axis of the motor housing 302, the central axis of the permanent magnet 303 and the central axis of the ceramic shaft 304 are coincident; the gap between the upper blade 3012 and the inner wall of the first arc-shaped groove is 0.05 mm-0.2 mm; the size of the first arc-shaped groove along the radius direction is 1.2-1.8 times of the length of the upper blade 3012, and the axial size of the first arc-shaped groove is 1.6-2.5 times of the distance between the opposite edges of the upper blade 3012 and the lower blade 3014; the upper blade 3012 has the same structure as the lower blade 3014.

The stator assembly 6 is arranged in the base 7 and comprises a silicon steel sheet 601 and a winding 602, and the winding 602 is arranged on the silicon steel sheet 601. In this embodiment, the stator assembly 6 is cylindrical and connected to the controller 8, the controller 8 is configured to control the stator assembly 6 to generate a rotating magnetic field under the action of current, the permanent magnet 303 is driven by the rotating magnetic field to drive the rotor assembly 3 to rotate together, and the rotating impeller 301 applies work to the fluid, so that the pressure of the fluid is increased. Specifically, the upper blade 3012 and the lower blade 3014 rotate to apply work to the fluid, the fluid leaves the blade region and enters the arc-shaped groove under the action of centrifugal force, and because the speed of the fluid in the arc-shaped groove is lower than that of the fluid in the impeller region, the speed of the fluid entering the arc-shaped groove will be reduced, the pressure will be raised, and the fluid enters the root of the blade under the guiding action of the inner wall of the arc-shaped groove; meanwhile, due to the guiding effect of the blade separation body 3013, the upper and lower fluid flows of the blade separation body 3013 do not generate impact, and the internal loss of the fluid is reduced.

Referring to fig. 5 and 6, a plurality of positioning posts 711 are disposed on the base 7, and the positioning posts 711 are received in the positioning holes 107 to position the base 7 and the volute 1; in this embodiment, the positions and shapes of the positioning posts 711 correspond to the positions and shapes of the positioning holes 107, respectively.

The base 7 is substantially rectangular, and is provided with a second pump cavity 701, and the second pump cavity 701 and the first pump cavity 101 jointly form a pump cavity of the micro pump. The second pump chamber 702 includes an annular second recess and a second arc-shaped slot, which is in communication with the second recess. The second groove penetrates through the bottom surface of the second arc-shaped groove. In this embodiment, the first arc-shaped groove and the second arc-shaped groove are corresponding in position, and both form an annular U-shaped groove (i.e., the arc-shaped groove). In this embodiment, the blade separator 3013 is disposed opposite to the connection between the first arc-shaped slot and the second arc-shaped slot; the U-shaped groove is used for accommodating the blade and the blade separating body 3013, and the first groove and the second groove are used for accommodating the impeller base 301.

The base 7 further comprises a base protrusion 707, and the base protrusion 707 is disposed on the bottom surface of the second arc-shaped groove. A third drainage groove 708 and a fourth drainage groove 709 are further formed in the base 7, one end of the third drainage groove 708 and one end of the fourth drainage groove 709 are respectively communicated with the second arc-shaped grooves, and the third drainage groove 708 and the fourth drainage groove 709 are arranged at intervals. The base protrusion 707 is located between the third and fourth drainage slots 708, 709 to isolate the third and fourth drainage slots 708, 709; the positions and shapes of the third drainage groove 708 and the fourth drainage groove 709 correspond to the positions and shapes of the first drainage groove 103 and the second drainage groove 104, respectively, so as to form two spaced drainage grooves, and the central axes of the two drainage grooves are located in the same plane.

The base 7 is further provided with a bearing hole 704, the central axis of the bearing hole 704 coincides with the central axis of the second groove, the wear-resistant sheet 5 is arranged on the bottom surface of the bearing hole 704, the bearing 4 is arranged in the bearing hole 704, and one end of the ceramic shaft 304, which is provided with the retainer ring 305, penetrates through the bearing 4 and is then accommodated in the bearing hole 704.

The base 7 is further provided with a plurality of screw holes 710, the positions of the plurality of screw holes 710 correspond to the positions of the plurality of screw holes 106, and one end of the screw 9 passes through the screw hole 106 and then extends into the screw hole 710 to form a threaded connection with the screw hole 710, so that the volute 1 is connected with the base 7.

A stator groove 702 and a control circuit groove 703 are further formed in one end, opposite to the volute 1, of the base 7, the stator groove 702 is annular, and the stator assembly 6 is contained in the stator groove 702. The controller 8 is disposed in the control circuit slot 703.

The base 7 is further provided with a water outlet 705 and a water inlet 706 at intervals, the water outlet 705 and the water inlet are respectively communicated with the two drainage grooves, and a central axis of the water outlet 705 and a central axis of the water inlet 706 are located in the same plane.

When the impeller 301 rotates counterclockwise, as shown in fig. 8, fluid enters the pump cavity from the water inlet 706 through the guiding action of the drainage grooves, the impeller 301 rotates to apply work to the fluid, so that the fluid has a velocity in the circumferential direction, and simultaneously, due to the action of centrifugal force, the fluid enters and exits the pump cavity for multiple times, and each time the fluid enters and exits the pump cavity, the fluid obtains energy from the blades, and the pressure is increased, so that the micro pump has a high lift. In addition, due to the circular motion and the longitudinal motion, the fluid in the pump chamber takes on a spiral motion as shown in fig. 8, and the fluid after being boosted pressure flows out of the micro pump through the corresponding drainage groove and the water outlet 705 in sequence. In this embodiment, the pump chamber and the impeller 301 are both symmetrical structures, and when the impeller 301 rotates clockwise, the micro pump can still work normally, and the fluid flowing direction is opposite to that in the counterclockwise direction.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A vortex micropump, characterized in that:

the micropump comprises a volute (1), a rotor assembly (3), a stator assembly (6) and a base (7), wherein the volute (1) is connected to the base (7), and a pump cavity is formed by the volute and the base; the rotor component (3) is accommodated in the pump cavity and is rotationally connected with the base (7); the stator assembly (6) is arranged in the base (7), and the rotor assembly (3) is sleeved outside the stator assembly (6);

the rotor assembly (3) comprises a columnar impeller (301), the impeller (301) is rotationally connected to the base (7) and comprises an impeller base body (3011), a plurality of upper blades (3012), a plurality of lower blades (3014) and an annular blade separating body (3013), the blade separating body (3013) is arranged on the outer circumference of the impeller base body (3011), the upper blades (3012) and the lower blades (3014) are respectively arranged on the blade separating body (3013), and the upper blades (3012) and the lower blades (3014) are respectively located on two opposite sides of the blade separating body.

2. The scroll micropump of claim 1, wherein: a stepped first pump cavity (101) is formed in the volute (1), the first pump cavity (101) comprises a first groove and a first arc-shaped groove which are communicated, and the first groove penetrates through the bottom surface of the first arc-shaped groove; a second pump cavity (701) is formed on the base (7), the second pump cavity (701) and the first pump cavity (101) jointly form the pump cavity, the pump cavity comprises a second groove and a second arc-shaped groove which are communicated, and the second groove penetrates through the bottom surface of the second arc-shaped groove and is annular; the first arc-shaped groove and the second arc-shaped groove form an annular U-shaped groove together, and the upper blade (3012), the lower blade (3014) and the blade separating body (3013) are contained in the U-shaped groove.

3. The scroll micropump of claim 2, wherein: the shape of the U-shaped groove is matched with that of the impeller (301); the clearance between the upper blade (3012) and the inner wall of the U-shaped groove is 0.05 mm-0.2 mm.

4. The scroll micropump of claim 3, wherein: the rotor component (3) is of a symmetrical structure, and the blade separating body (3013) is arranged opposite to a connecting part between the upper blade (3012) and the lower blade (3014).

5. The scroll micropump of claim 2, wherein: a first drainage groove (103) and a second drainage groove (104) which are arranged at intervals are formed in the volute (1), and one end of the first drainage groove (103) and one end of the second drainage groove (104) are communicated with the first arc-shaped groove; the volute (1) further comprises a volute (1) protrusion (102), the volute (1) protrusion (102) is arranged on the bottom surface of the first arc-shaped groove and is located between the first drainage groove (103) and the second drainage groove (104) to partition the first drainage groove (103) and the second drainage groove (104), and direct communication of fluid in the first drainage groove (103) and fluid in the second drainage groove (104) is avoided.

6. The scroll micropump of claim 5, wherein: third drainage grooves (708) and fourth drainage grooves (709) which are arranged at intervals are formed in the base (7), and one ends of the third drainage grooves (708) and one ends of the fourth drainage grooves (709) are respectively communicated with the second arc-shaped grooves; the base (7) further comprises a base protrusion (707), the base protrusion (707) being located between the third and fourth drainage slots (708, 709) to isolate the third and fourth drainage slots (708, 709); the positions and the shapes of the third drainage groove (708) and the fourth drainage groove (709) correspond to the positions and the shapes of the first drainage groove (103) and the second drainage groove (104) respectively so as to form two spaced drainage grooves, and the two drainage grooves are used for providing a passage for fluid to enter and exit the U-shaped groove.

7. The scroll micropump of claim 2, wherein: the rotor assembly (3) further comprises a motor shell (302) and a permanent magnet (303), wherein the annular permanent magnet (303) is arranged in the annular motor shell (302); the impeller base body (3011) is provided with an accommodating groove, the motor shell (302) is arranged in the accommodating groove, and the permanent magnet (303) is sleeved outside the stator assembly (6).

8. The scroll micropump of claim 7, wherein: the rotor assembly (3) further comprises a ceramic shaft (304) and a collar (305), the collar (305) being disposed on one end of the ceramic shaft (304); the micropump further comprises a bearing and a wear-resistant sheet, the base (7) is provided with a bearing hole (704), a bearing (4) is arranged in the bearing hole (704), one end, provided with the clamping ring (305), of the ceramic shaft (304) penetrates through the bearing (4) and then extends into the bearing hole (704), and the wear-resistant sheet is arranged between the ceramic shaft (304) and the bottom surface of the bearing hole (704); the other end of the ceramic shaft (304) is connected to the impeller (301).

9. The scroll micropump of claim 8, wherein: a stator groove (702) is further formed in one end, far away from the volute (1), of the base (7), the stator assembly (6) is arranged in the stator groove (702), and the central axis of the stator assembly (6), the central axis of the rotor assembly (3) and the central axis of the ceramic shaft (304) are overlapped.

10. The scroll micropump of any one of claims 1-9, wherein: the micropump further comprises a controller (8) and a sealing member (2), the controller (8) being connected to the base (7) for controlling the stator assembly (6); the volute casing (1) is further provided with a sealing piece groove (105), and the sealing piece (2) is contained in the sealing piece groove (105) and is located between the volute casing (1) and the base (7).