Fluid pump

Abstract

The present application discloses a fluid pump, comprising a pump casing, and an impeller and a motor connected to the impeller, wherein the impeller and the motor are arranged in the pump casing. The motor comprises a stator assembly and a rotor assembly. The impeller is connected to the rotor assembly. The stator assembly comprises a stator casing, a stator magnetic core disposed in the stator casing, a coil wound on the stator magnetic core, a conductive terminal electrically connected to the coil, a terminal support part for supporting the conductive terminal, and a circuit board electrically connected to the conductive terminal. A partition plate is disposed in the stator casing. The partition plate divides the internal space of the stator casing into a first space and a second space. The coil and the circuit board are arranged in the first space and the second space, respectively. The partition plate is recessed towards the circuit board to form a receiving slot for accommodating the terminal support part. One end of the conductive terminal in the axial direction is located in the terminal support part, and the other end thereof in the axial direction passes through the bottom of the receiving slot and is then connected to the circuit board. According to the present application, heat of the coil can be effectively prevented from radiating towards the circuit board, and further the temperature of the circuit board is effectively controlled.

Description

Fluid pumps Technical Field

[0001] The present application relates to a pump, and in particular to a fluid pump. Background Art

[0002] A fluid pump typically consists of a pump housing, an impeller rotatably mounted within the pump housing, and a motor that drives the impeller. During operation, the motor's coils generate significant heat, which then radiates to the circuit board, causing it to overheat and malfunction.

[0003] Summary of the Invention

[0004] In view of this, a fluid pump is provided that can effectively control the temperature of a circuit board.

[0005] A fluid pump comprises a pump casing, an impeller arranged in the pump casing, and a motor connected to the impeller, the motor comprising a stator assembly and a rotor assembly, the impeller being connected to the rotor assembly, the stator assembly comprising a stator casing, a stator core arranged in the stator casing, a coil wound on the stator core, a conductive terminal electrically connected to the coil, a terminal support portion for supporting the conductive terminal, and a circuit board electrically connected to the conductive terminal, the stator casing being provided with a partition, the partition dividing the internal space of the stator casing into a first space and a second space, the coil and the circuit board being arranged in the first space and the second space respectively, the partition being recessed toward the circuit board to form a avoidance groove for accommodating the terminal support portion, one axial end of the conductive terminal being located in the terminal support portion, and the other axial end passing through the bottom of the avoidance groove and then connected to the circuit board.

[0006] Compared with the existing technology, the fluid pump provided in this application separates the coil and the circuit board through a partition to prevent the heat of the coil from dissipating toward the circuit board; in addition, the partition is recessed toward the circuit board to form an avoidance groove to accommodate the terminal support portion, so that the bottom of the avoidance groove of the partition only needs to be provided with a small perforation that is adapted to the size of the conductive terminal, further preventing the heat of the coil from dissipating toward the circuit board, effectively controlling the temperature of the circuit board, and avoiding malfunctions due to excessive temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIG1 is a schematic structural diagram of a fluid pump according to a preferred embodiment of the present application.

[0008] FIG2 is a plan view of the fluid pump shown in FIG1.

[0009] FIG3 is a cross-sectional view of the fluid pump shown in FIG2 along line III-III.

[0010] FIG4 is an enlarged view of circle IV in FIG3 .

[0011] FIG5 is a cross-sectional view of the fluid pump shown in FIG2 along line VV.

[0012] FIG6 is an exploded view of the fluid pump shown in FIG1 .

[0013] FIG. 7 is a further exploded view of the impeller of the fluid pump shown in FIG. 6 .

[0014] FIG. 8 is a plan view of a stator housing of the motor of the fluid pump shown in FIG. 6 .

[0015] FIG9 is a perspective cross-sectional view of the stator housing.

[0016] FIG10 is a plan view of the stator inner housing and the motor shaft of the motor of the fluid pump shown in FIG6 .

[0017] FIG11 is a three-dimensional cross-sectional view of the stator inner shell and the motor shaft.

[0018] FIG12 is a diagram showing the stator core, insulating frame, coils and conductive terminals of the motor of the fluid pump shown in FIG6 from another angle.

[0019] FIG13 is a plan view of the stator core, insulating frame, coils, and conductive terminals shown in FIG12.

[0020] FIG. 14 is a further exploded view of the rotor assembly of the motor of the fluid pump shown in FIG. 6 .

[0021] FIG. 15 is a view of the pump housing of the fluid pump shown in FIG. 6 from another angle.

[0022] Description of Figure Numbers:

[0023] 10. Pump casing; 12. Inlet; 14. Outlet; 16. Second shaft seat;

[0024] 20. Impeller; 22. Bottom plate; 24. Cover plate; 26. Blades;

[0025] 30. Motor; 32. Stator assembly; 320. First shaft seat; 320a. Notch; Stator housing; 322. Connecting portion; 323. Stator inner housing; 324a. First rib; 324b. Second rib; 325. Stator core; 326. Insulating frame; 3261. Terminal support; 327. Coil; 328. Conductive terminal; 329. Circuit board; 34. Rotor assembly; 342. Support body; 343. Rotor core; 345. Permanent magnet; 347. Shaft hole; 36. End cap; 38. Partition; 381. First space; 383. Second space; 385. Avoidance groove; 387. Perforation;

[0026] 40 / 42 / 44, thermal conductive medium;

[0027] 50 / 52 / 54, sealing ring;

[0028] 60, motor shaft; 62 guide groove;

[0029] 70. Gasket; 72. Groove.

[0030] DETAILED DESCRIPTION

[0031] To facilitate understanding of the present application, a more comprehensive description of the present application will be provided below with reference to the accompanying drawings. The accompanying drawings provide exemplary embodiments of the present application to provide a more accurate and thorough understanding of the technical solutions disclosed herein. However, it should be understood that the present application can be implemented in a variety of different forms and is not limited to the embodiments described below.

[0032] The same or similar numbers in the drawings of this application correspond to the same or similar parts; in the description of this application, it should be understood that if there are terms such as "up", "down", "left", "right", etc. indicating directions or positional relationships, they are based on the directions or positional relationships shown in the drawings. This is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting this application. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0033] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, scheme B, or schemes in which A and B are satisfied at the same time.

[0034] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0035] The present application provides a fluid pump, such as a water pump, etc. FIG1-6 show a specific embodiment of the fluid pump of the present application, wherein the pump includes a pump housing 10 , an impeller 20 disposed in the pump housing 10 , and a motor 30 driving the impeller 20 to rotate in the pump housing 10 .

[0036] As shown in Figure 1, the pump housing 10 is provided with an inlet 12 and an outlet 14. The inlet 12 and outlet 14 are respectively used to connect to external pipelines to form a flow path for the fluid. In this embodiment, the inlet 12 extends axially along the pump housing 10, and the outlet 14 extends approximately tangentially to the outer circumference of the pump housing 10. In other words, the inlet 12 and outlet 14 are approximately perpendicular.

[0037] Please also refer to Figure 7. The impeller 20 is a disc-shaped structure as a whole, including a base plate 22 and a cover plate 24 that are relatively spaced apart, with a number of blades 26 disposed between the base plate 22 and the cover plate 24. The diameter of the impeller 20 as a whole is slightly smaller than the inner diameter of the pump casing 10, and there is a gap between the two, so that the impeller 20 can rotate freely in the pump casing 10 and push the fluid toward the outlet 14. Preferably, the blades 26 and the base plate 22 are integrally injection molded, and the cover plate 24 is connected to the base plate 22 by means of a snap or the like. In some embodiments, the cover plate 24 and the base plate 22 can also be connected by ultrasonic welding or bonding. In some embodiments, the cover plate 24 and the base plate 22 can also be an integral structure.

[0038] As shown in Figure 6, in this embodiment, the motor 30 is an internal rotor motor, comprising a stator assembly 32 and a rotor assembly 34 rotatably disposed within the stator assembly 32. The stator assembly 32 is connected to the pump housing 10, and the rotor assembly 34 is connected to the impeller 20, preferably forming an integral structure. Upon startup of the motor 30, the rotor assembly 34 rotates axially relative to the stator assembly 32, driving the connected impeller 20 to rotate within the pump housing 10.

[0039] Referring also to Figures 8-11 , the stator assembly 32 includes a stator outer shell 321, a stator inner shell 323, a stator core 325 disposed between the stator inner shell 323 and the stator outer shell 321, a coil 327 wound around the stator core 325, a conductive terminal 328 electrically connected to the coil 327, and a terminal support 3261 for supporting the conductive terminal 328. The stator assembly 32 is electrically connected to a circuit board 329 via the conductive terminal 328. After the motor is started, the circuit board 329 supplies current to the coil 327 and controls the direction and magnitude of the current flowing in the coil 327, enabling the stator assembly 32 to generate a periodically changing rotating magnetic field. This magnetic field interacts with the permanent magnets of the rotor assembly 34, driving the rotor assembly 34 to rotate, thereby driving the impeller 20 to rotate.

[0040] As shown in Figures 8-9, the stator outer shell 321 is a generally cylindrical structure with two open ends, including a first end (e.g., the top end) and a second end (e.g., the bottom end) that are axially opposed. The first end is connected to the pump housing 10 via a fastener, such as a screw, while the second end is connected to the end cap 36 via a fastener, such as a screw, or alternatively, ultrasonic welding, friction welding, or other adhesive methods. As shown in Figures 10-11, the stator inner shell 323 is a generally cylindrical structure, including an open end (e.g., the top end) and a closed end (e.g., the bottom end) that are axially opposed. The open end faces the pump housing 10, while the closed end faces the end cap 36. The outer diameter of the stator inner shell 323 is smaller than the inner diameter of the stator outer shell 321. After assembly, the stator inner shell 323 is disposed within the stator outer shell 321, with the two being radially spaced apart. The rotor assembly 34 is rotatably disposed within the stator inner shell 323 (see Figure 3).

[0041] As shown in Figures 3, 4, and 9, a partition 38 is disposed between the inner wall of the stator outer shell 321 and the outer wall of the stator inner shell 323. The partition 38 is positioned relatively close to the closed end of the stator inner shell 323 and away from its open end. In this embodiment, the partition 38 is integrally formed by extending radially toward the stator inner shell 323 from the inner wall of the stator outer shell 321 near the second side end. Preferably, the inner diameter of the partition 38 is comparable to the outer diameter of the stator inner shell 323 to ensure that the partition 38 fits as closely as possible against the outer wall of the stator inner shell 323 and minimize the gap between the two. A heat-conducting medium, such as the heat-conducting medium 40 (see Figure 4), may be interposed between the partition 38 and the circumferential outer wall of the stator inner shell 323 to transfer heat from the partition 38 through the stator inner shell 323 to the fluid flowing into the stator inner shell 323. Preferably, the heat conducting medium 40 surrounds the circumferential outer wall of the stator inner shell 323 , thereby closing the gap between the partition plate 38 and the stator inner shell 323 .

[0042] By setting the partition 38, the space between the stator outer shell 321 and the stator inner shell 323 is divided into two relatively independent parts. Among them, on the upper side of the partition 38, the radial gap between the stator outer shell 321 and the stator inner shell 323 serves as a first space 381 for installing the stator core 325 and the coil 327; on the lower side of the partition 38, the part surrounded by the stator outer shell 321 and the end cover 36 serves as a second space 383 for installing the circuit board 329.

[0043] In some embodiments, the partition 38 can also be formed separately and then assembled to the corresponding position of the stator outer shell 321 and / or the stator inner shell 323, as long as the first space 381 and the second space 383 can be separated to achieve a heat insulation effect between the coil 327 and the circuit board 329.

[0044] As shown in Figures 8-9, the outer edge of the partition 38 is recessed toward the circuit board 329 to form a relief groove 385 for accommodating the terminal support portion 3261. One axial end of the conductive terminal 328 is located within the terminal support portion 3261 and electrically connected to the coil 327. The other axial end extends through the bottom of the relief groove 385 and is connected to the circuit board 329. The motor 30 is preferably a three-phase motor, with three or four conductive terminals 328. The partition 38 has three or four through-holes 387 at the bottom of its relief groove 385, corresponding to the conductive terminals 328. As shown in Figure 8, in this embodiment, the partition 38 has three through-holes 387 at the bottom of its relief groove 385. Preferably, the central angle α corresponding to the relief groove 385 is no greater than 120 degrees, meaning that the length of the relief groove 385 along the circumference of the partition 38 does not exceed one-third of the circumference.

[0045] As shown in Figures 5, 6, 12, and 13, an insulating frame 326 is disposed between the stator core 325 and the coil 327. The insulating frame 326 projects toward the circuit board 329 corresponding to each conductive terminal 328, forming a terminal support portion 3261. The provision of the clearance slots 385 allows the partition 38 to effectively clear the terminal support portions 3261. Therefore, the size of the through-holes 387 is not limited by the size of the terminal support portions 3261; they only need to allow the ends of the conductive terminals 328 to pass through.

[0046] Compared to the prior art, the present application utilizes a partition 38 to separate a first space 381 for mounting the coil 327 from a second space 383 for mounting the circuit board 329, thereby reducing the amount of heat generated by the coil 327 dissipated toward the circuit board 329. Furthermore, the partition 38 is recessed toward the circuit board 329 to form a relief groove 385 to clear the terminal support portion 3261. This allows the bottom of the relief groove 385 of the partition 38 to be formed with only a small perforation 387 that matches the size of the end of the conductive terminal 328. This further reduces the amount of heat dissipated from the coil 327 toward the circuit board 329, effectively lowering the temperature of the circuit board 329.

[0047] To minimize heat transfer from coil 327 to circuit board 329 through perforations 387 of partition plate 38, in one embodiment, as shown in FIG8 , the cross-sectional dimensions of perforations 387 are configured to have a length L0 no greater than 3.0 mm and a width W0 no greater than 2.0 mm. As shown in FIG12-13 , the cross-sectional dimensions of terminal support portion 3261 are configured to have a length L1 and a width W1, where L1 > L0 and W1 > W0.

[0048] As shown in Figure 4 , the terminal support portion 3261 extends into the relief groove 385 of the partition plate 38, with its end surface positioned as close as possible to the bottom of the relief groove 385 to minimize the axial spacing between the two. In one embodiment, this spacing is set to no greater than 5.0 mm, allowing the terminal support portion 3261 to block the through-hole 387, further reducing or even preventing heat dissipation through the through-hole 387 toward the circuit board 329.

[0049] As shown in Figures 3-5, the circuit board 329 is in thermal contact with the closed end of the stator inner shell 323. Preferably, the circuit board 329 abuts the axially outer end surface of the closed end of the stator inner shell 323, with a thermally conductive medium 42 filling the space between them. This allows heat from the circuit board 329 to be quickly transferred toward the closed end of the stator inner shell 323 and then dissipated to the outside through the flow of fluid flowing into the stator inner shell 323. The thermal contact between the circuit board 329 and the closed end of the stator inner shell 323 eliminates the need to consider heat dissipation requirements during the design of the end cap 36, allowing for greater flexibility in material selection, such as the use of low-cost plastic.

[0050] In other embodiments, the circuit board 329 may also be in thermal contact with the circumferential outer wall of the closed end of the stator inner shell 323. Specifically, the stator assembly 32 further includes a cylindrical metal cover (not shown) with a bottom. The metal cover is fixed to the closed end of the stator inner shell 323 and is in thermal contact with the circumferential outer wall of the closed end of the stator inner shell 323. The circuit board 329 is in thermal contact with the bottom of the metal cover, thereby transferring heat from the circuit board 329 to the fluid in the stator inner shell 323 via the cylindrical portion of the metal cover and the circumferential outer wall of the stator inner shell 323.

[0051] To facilitate thermal contact between the circuit board 329 and the stator inner shell 323 , the electronic components on the circuit board 329 are arranged on the side of the circuit board 329 facing away from the stator inner shell 323 .

[0052] The open end of the stator inner shell 323 extends radially outward to form an annular connecting portion 322. The outer diameter of the connecting portion 322 is comparable to the outer diameters of the stator outer shell 321 and the pump housing 10. During assembly, as shown in Figure 3, the outer edge of the connecting portion 322 is sandwiched between the stator outer shell 321 and the pump housing 10 and fixed together by screws or the like. Preferably, a sealing ring 50 is sandwiched between the connecting portion 322 and the pump housing 10, so that the pump housing 10 and the stator inner shell 323 form a sealed space, and the fluid flowing through the pump housing 10 will not leak outward. Preferably, a sealing ring 44 is sandwiched between the connecting portion 322 and the stator outer shell 321, and a sealing ring 54 is sandwiched between the stator outer shell 321 and the end cover 36, so that the first space 381 and the second space 383 are sealed as a whole.

[0053] As shown in Figure 3, preferably, a heat-conducting medium 44 is provided between the coil 327 and the stator inner shell 323, such as the connecting portion 322 of the stator inner shell 323, so that the heat generated by the coil 327 can also be quickly conducted to the stator inner shell 323 and then dissipated outward through the flowing fluid.

[0054] In this embodiment, the stator outer shell 321 and the stator inner shell 323 are separately formed and assembled together to form the stator shell of the stator assembly 32. In some embodiments, the stator outer shell 321 and the stator inner shell 323 can also be an integrated structure, which is not limited to the specific embodiment.

[0055] As shown in Figure 14, the rotor assembly 34 includes a support body 342, a rotor core 343 embedded in the support body 342, and a permanent magnet 345 fixed to the outer peripheral side of the rotor core 343. An axial hole 347 is provided in the center of the support body 342 for passing the motor shaft 60. In this embodiment, the stator inner shell 323 forms a first shaft seat 320 in the center of its closed end, and the pump housing 10 is provided with a second shaft seat 16 in the center of its inner side. The rotor assembly 34 is rotatably sleeved on the middle part of the motor shaft 60, and the two ends of the motor shaft 60 are respectively placed in the first and second shaft seats 320 and 16. Among them, at least one end of the motor shaft 60 is fixedly connected to one of the shaft seats 320 or 16. Preferably, one end of the motor shaft 60 is fixedly connected to the first shaft seat 320, preferably integrally formed in the first shaft seat 320; the other end is loosely connected to the second shaft seat 16.

[0056] As shown in Figures 10-11, the stator inner shell 323 is preferably provided with a plurality of first ribs 324a therein. The first ribs 324a are preferably evenly spaced along the circumference. Each first rib 324a is generally triangular in structure, with one side connected to the circumferential inner wall of the stator inner shell 323 and the other side connected to the axial inner end surface of the closed end of the stator inner shell 323. This enhances the strength of the stator inner shell 323 and better supports the rotation of the rotor assembly 34.

[0057] The stator inner shell 323 may also be internally provided with a plurality of second ribs 324b, preferably evenly spaced along the circumference. Each second rib 324b is roughly triangular in structure, with one side connected to the circumferential outer wall of the shaft seat 320 and the other side connected to the axial inner end surface of the closed end of the stator inner shell 323, thereby enhancing the strength of the shaft seat 320. The radial spacing of the first and second ribs 324a, 324b allows for better heat transfer from the circuit board 329 to the fluid through the closed end of the stator inner shell 323.

[0058] The circuit board 329 houses multiple high-heat-generating electronic components, such as a microprocessor for controlling motor speed, electrolytic capacitors for power smoothing and filtering, a filter inductor for electromagnetic interference shielding, and multiple switching elements for the inverter. Each of these high-heat-generating components is at least partially positioned away from the location corresponding to the shaft seat 320 and arranged in an annular area outside the shaft seat 320, corresponding to the closed end of the stator inner housing 323, to better conduct heat through the closed end of the stator inner housing 323 to the fluid.

[0059] As shown in Figures 5, 6 and 11, preferably, a guide groove 62 is formed on the outer circumferential surface of the motor shaft 60, and the guide groove 62 extends along the axial direction of the motor shaft 60 to both ends of the motor shaft 60, connecting the spaces on both sides of the rotor assembly 34 in the axial direction, so that the fluid can flow between the impeller 20 and the stator inner shell 323 of the motor 30 along the path indicated by the arrow in Figure 5. Preferably, a notch 320a is provided at the outer end of the shaft seat 320, and the fluid can flow into the guide groove 62 of the shaft seat 320 through the notch 320a, and then flow along the guide groove 62 toward the impeller 20. In the illustrated embodiment, the guide groove 62 is single. In other embodiments, there may be multiple guide grooves 62 and they may be arranged at intervals along the circumference of the motor shaft 60.

[0060] As shown in Figures 5, 6, and 15, a gasket 70 is preferably sleeved on the end of the motor shaft 60 connected to the pump housing 10. The gasket 70 is connected to the shaft seat 16 and faces the location of the impeller 20. A groove 72 is formed on the axial end surface of the gasket 70 facing away from the pump housing 10. The groove 72 extends radially, connecting the inner side with the guide groove 62 of the motor shaft 60 and the outer side with the space within the pump housing 10. When the fluid flows upward along the guide groove 62 of the motor shaft 60 to the gasket 70, it can flow outward along the groove 72 and return to the impeller 20. In the illustrated embodiment, there are multiple grooves 72, spaced apart along the circumference of the gasket 70. In other embodiments, there can be a single groove 72. In other embodiments, radial holes or radial grooves, etc., can be provided on other components to replace the groove 72, as long as the fluid in the guide groove 62 can flow outward through the radial holes or radial grooves and return to the impeller 20.

[0061] When the fluid pump of this embodiment is in operation, fluid enters through the inlet 12 of the pump housing 10 and, driven by the rotation of the impeller 20, flows out through the outlet 14. As shown by the arrows in Figure 5, some of the fluid flows through the gap between the outer periphery of the rotor assembly 34 and the stator inner housing 323 to the bottom space of the stator inner housing 323, absorbing heat from the circuit board 329, which is in thermal contact with the stator inner housing 323. The fluid, after absorbing heat, enters the guide groove 62 of the motor shaft 60 through the notch 320a of the shaft seat 320 and flows upward along the guide groove 62. It then flows along the groove 72 of the gasket 70 to the impeller 20 and is discharged from the outlet 14 of the pump housing 10 under the action of the impeller 20. The fluid flowing along this path can transfer the heat generated by the operation of the motor 30 into the fluid and dissipate it to the outside world, further improving the heat dissipation effect, allowing the circuit board 329 to operate at an appropriate temperature, avoiding malfunctions, and improving electrical safety.

[0062] It should be noted that the above embodiments merely represent preferred implementations of the present application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the present application. It should be noted that those skilled in the art may, without departing from the spirit of the present application, make various modifications and improvements, such as combining different features from the various embodiments, and all of these modifications and improvements should fall within the scope of protection of the present application.

Claims

1. A fluid pump, comprising a pump housing, an impeller disposed in the pump housing, and a motor connected to the impeller, wherein the motor comprises a stator assembly and a rotor assembly, the impeller is connected to the rotor assembly, and is characterized in that: The stator assembly includes a stator shell, a stator core arranged in the stator shell, a coil wound on the stator core, a conductive terminal electrically connected to the coil, a terminal support part for supporting the conductive terminal, and a circuit board electrically connected to the conductive terminal. The stator shell is provided with a partition, which divides the internal space of the stator shell into a first space and a second space. The coil and the circuit board are respectively arranged in the first space and the second space. The partition is recessed toward the direction of the circuit board to form an avoidance groove for accommodating the terminal support part. One axial end of the conductive terminal is located in the terminal support part, and the other axial end passes through the bottom of the avoidance groove and is connected to the circuit board.

2. The fluid pump according to claim 1, characterized in that An insulating frame is provided between the coil and the stator core, and the insulating frame protrudes toward the partition to form the terminal supporting portion.

3. The fluid pump according to claim 1, characterized in that: The bottom of the avoidance groove of the partition is provided with a through hole for penetrating the conductive terminal, and the cross-sectional dimension of the through hole is smaller than the cross-sectional dimension of the terminal support portion.

4. The fluid pump according to claim 3, characterized in that: The axial spacing between the terminal support portion and the bottom of the avoidance groove does not exceed 5.0 mm, and the length of the through hole is not greater than 3.0 mm and the width is not greater than 2.0 mm.

5. The fluid pump according to claim 3, characterized in that: The motor is a three-phase motor, the number of the conductive terminals is three or four, and the bottom of the avoidance groove of the partition is correspondingly provided with three or four through holes for penetrating the ends of the three or four conductive terminals.

6. The fluid pump according to any one of claims 1 to 5, characterized in that: The stator shell includes a cylindrical stator outer shell and a stator inner shell, wherein the stator inner shell is arranged in the stator outer shell and is radially spaced from the stator outer shell, the rotor assembly is arranged in the stator inner shell, and the partition is located between the inner wall of the stator outer shell and the outer wall of the stator inner shell.

7. The fluid pump according to claim 6, characterized in that The stator inner shell comprises an open end and a closed end which are opposite to each other in the axial direction. The open end faces the pump shell, and the axial outer end surface or the circumferential outer wall of the closed end is in thermal contact with the circuit board.

8. The fluid pump according to claim 7, characterized in that The rotor assembly is rotatably sleeved on the motor shaft; a shaft seat is formed in the center of the closed end of the stator inner shell, one end of the motor shaft is arranged in the shaft seat and fixedly connected to the shaft seat, and the electronic components on the circuit board are arranged on the side of the circuit board away from the closed end of the stator inner shell; the components with high heat generation in the electronic components include a microprocessor for controlling the motor speed, an electrolytic capacitor for power smoothing and filtering, a filter inductor for shielding electromagnetic interference, and a plurality of switch elements constituting an inverter; each of the components with high heat generation at least partially avoids the position corresponding to the shaft seat and is arranged in an annular area outside the shaft seat corresponding to the closed end of the stator inner shell.

9. The fluid pump according to claim 7, characterized in that: The stator assembly further includes a cylindrical metal cover with a bottom, the metal cover is fixed to the closed end of the stator inner shell and is in thermal contact with the circumferential outer wall of the closed end of the stator inner shell, and the circuit board is in thermal contact with the bottom of the metal cover, so that the heat of the circuit board is conducted to the fluid in the stator inner shell via the cylindrical portion of the metal cover and the circumferential outer wall of the stator inner shell.

10. The fluid pump according to claim 6, characterized in that The stator outer shell is a cylindrical structure with two ends open, one end of which is sealed to the stator inner shell and the other end is sealed to an end cover, the partition is formed by integrally extending from the inner wall of the stator outer shell toward the stator inner shell, the open end of the stator inner shell extends radially outward to form an annular connecting portion, and the outer edge of the connecting portion is sandwiched between the stator outer shell and the pump shell.

11. The fluid pump according to claim 6, characterized in that A heat-conducting medium is arranged between the partition and the circumferential outer wall of the stator inner shell to conduct the heat on the partition to the fluid flowing into the stator inner shell through the stator inner shell.

12. The fluid pump according to claim 11, characterized in that The heat conducting medium surrounds the circumferential outer wall of the stator inner shell, thereby closing the gap between the partition plate and the stator inner shell.

13. The fluid pump according to claim 6, characterized in that The rotor assembly is rotatably sleeved on the motor shaft, a shaft seat is formed in the center of the closed end of the stator inner shell, one end of the motor shaft is arranged in the shaft seat and fixedly connected to the shaft seat; the motor shaft is provided with an axially extending guide groove, so that the fluid can flow along the guide groove from the end of the motor shaft close to the shaft seat to the impeller.

14. The fluid pump according to claim 13, characterized in that The shaft seat of the stator inner shell is provided with a notch so that the fluid can flow into the guide groove through the notch.

15. The fluid pump according to claim 13, characterized in that A gasket is sleeved on one end of the motor shaft facing the pump housing, and a radial groove is provided on the axial side of the gasket away from the pump housing, so that the fluid can flow from the guide groove along the groove to the impeller.

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