Stator assembly fixing structure and its application in electronic water pumps

Abstract

This invention discloses a stator assembly fixing structure and an electronic water pump using the same. The electronic water pump includes at least a pump casing and a stator assembly. The pump casing forms a rotor chamber and a stator chamber sequentially from the inside out. An axial limiting step is formed in the stator chamber within the pump casing. The stator assembly and the stator chamber of the pump casing are provided with: one of them having a snap fastener, and the other having a locking position matching the shape of the snap fastener. After the stator assembly is installed into the stator chamber of the pump casing, at least a portion of the stator assembly abuts against the axial limiting step, and the snap fastener and locking position cooperate to force the stator assembly to exert force on the axial limiting step, thereby axially fixing the stator assembly in the stator chamber of the pump casing. This invention provides a reasonable, reliable, stable, and durable stator assembly fixing structure for electronic water pumps, ensuring that the stator assembly will not experience radial movement, and solving a series of problems such as instability of the rotating magnetic field, damage to the drive circuit board caused by stator assembly movement, and high operating noise.

Description

Technical Field

[0001] This invention relates to the field of electronic water pumps and their components, specifically to a stator assembly fixing structure and an electronic water pump using the same. Background Technology

[0002] Electric water pumps have high output efficiency and can achieve precise flow control. Therefore, they are widely used in automobiles, home appliances and industrial equipment. In particular, new energy vehicles usually have two or more electric water pumps. The electric water pump is the power source of the entire cooling system of new energy vehicles. The power battery, drive motor and other components of new energy vehicles all rely on the electric water pump to drive the coolant for circulation and cooling.

[0003] In existing electronic water pumps, the pump casing typically has a two-layer structure. The inner layer is the rotor chamber, in which the rotor assembly of the electronic water pump is housed. The outer layer is the stator chamber surrounding the rotor chamber. The flow channels of the rotor chamber are isolated from the stator chamber, and the stator assembly of the electronic water pump is housed in the stator chamber. The rotor assembly is equipped with permanent magnets (such as magnetic rings). When the stator assembly is energized, it can generate a rotating magnetic field in its internal cavity. This rotating magnetic field magnetically couples and drives the rotor assembly to rotate in the rotor chamber, which in turn drives the impeller connected to the rotor assembly to rotate. The rotating impeller drives the water flow.

[0004] To provide a stable rotating magnetic field, the stator assembly needs to be fixed in the stator chamber of the pump casing. In existing electronic water pumps, encapsulating adhesive is usually poured into the stator chamber where the stator assembly is assembled, and the stator assembly is fixed in the stator chamber by the cured encapsulating adhesive. If a rigid encapsulating adhesive is used, it is easy to cause the pump casing to crack during long-term use. If a soft encapsulating adhesive is used, the stator assembly is prone to axial movement during the use of the electronic water pump, which will cause a series of problems such as instability of the rotating magnetic field, damage to the drive circuit board (the drive circuit board is usually electrically connected to the stator assembly using terminals), and increased operating noise of the electronic water pump.

[0005] In conclusion, how to provide a reasonable, reliable, stable and durable stator assembly fixing structure for electronic water pumps has become an urgent problem to be solved. Summary of the Invention

[0006] The purpose of this invention is to provide a stator assembly fixing structure and an electronic water pump using the same, which can provide a reasonable, reliable, stable and durable stator assembly fixing structure for electronic water pumps.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a stator assembly fixing structure applied to an electronic water pump, wherein the electronic water pump includes at least a pump casing and a stator assembly; the pump casing forms a rotor chamber and a stator chamber sequentially from the inside to the outside; the pump casing forms an axial limiting step in the stator chamber; the stator assembly and the stator chamber of the pump casing are provided with: one of them is provided with a snap fastener, and the other is provided with a fastening position matching the shape of the snap fastener; after the stator assembly is installed into the stator chamber of the pump casing, at least a portion of the stator assembly abuts against the axial limiting step, and the snap fastener and the fastening position cooperate with each other to force the stator assembly to exert force on the axial limiting step, thereby axially fixing the stator assembly in the stator chamber of the pump casing.

[0008] In the above technical solution, the stator assembly and the stator chamber of the pump housing further include: at least one of them is provided with a potting groove; after the stator assembly is installed into the stator chamber of the pump housing, encapsulating adhesive is poured into the stator chamber of the pump housing, the liquid encapsulating adhesive can fill the potting groove, and the cured encapsulating adhesive can fix the stator assembly axially and / or radially in the stator chamber of the pump housing.

[0009] In the above technical solution, the stator assembly is provided with a snap fastener, and the stator chamber of the pump housing is provided with a snap-fit ​​position that matches the snap fastener.

[0010] In the above technical solution, the stator assembly includes a stator support and a coil wound on the stator support; at least a portion of the stator support extends to form the buckle.

[0011] In the above technical solution, the pump casing is provided with an inner wall portion and an outer wall portion from the inside out; the cavity inside the inner wall portion is the rotor chamber, and the cavity between the inner wall portion and the outer wall portion is the stator chamber; the axial limiting step is provided on the inner wall of the outer wall portion or the outer wall of the inner wall portion; the fastening position is opened on the inner wall of the outer wall portion or the outer wall of the inner wall portion; the glue filling groove is also opened on the inner wall of the outer wall portion or the outer wall of the inner wall portion.

[0012] A stator assembly fixing structure is applied to an electronic water pump, wherein the electronic water pump includes at least a pump housing and a stator assembly; the pump housing forms a rotor chamber and a stator chamber sequentially from the inside to the outside; the stator assembly and the stator chamber of the pump housing are provided with at least one of the following: a potting groove is provided; after the stator assembly is installed into the stator chamber of the pump housing, encapsulating adhesive is poured into the stator chamber of the pump housing, the liquid encapsulating adhesive can fill the potting groove, and the cured encapsulating adhesive can fix the stator assembly axially and / or radially in the stator chamber of the pump housing.

[0013] In the above technical solution, the pump casing forms an axial limiting step in the stator chamber; the stator assembly and the stator chamber of the pump casing are further provided with: one of them is provided with a buckle, and the other is provided with a fastening position that matches the shape of the buckle; after the stator assembly is installed into the stator chamber of the pump casing, at least a portion of the stator assembly abuts against the axial limiting step, and the buckle and the fastening position cooperate with each other to force the stator assembly to exert force on the axial limiting step, thereby axially fixing the stator assembly in the stator chamber of the pump casing.

[0014] In the above technical solution, the stator assembly is provided with a snap fastener, and the stator chamber of the pump housing is provided with a snap-fit ​​position that matches the snap fastener.

[0015] In the above technical solution, the stator assembly includes a stator support and a coil wound on the stator support; at least a portion of the stator support extends to form the buckle.

[0016] In the above technical solution, the pump casing is provided with an inner wall portion and an outer wall portion from the inside out; the cavity inside the inner wall portion is the rotor chamber, and the cavity between the inner wall portion and the outer wall portion is the stator chamber; the axial limiting step is provided on the inner wall of the outer wall portion or the outer wall of the inner wall portion; the fastening position is opened on the inner wall of the outer wall portion or the outer wall of the inner wall portion; the glue filling groove is also opened on the inner wall of the outer wall portion or the outer wall of the inner wall portion.

[0017] An electronic water pump includes the aforementioned stator assembly fixing structure.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: The stator assembly fixing structure of the present invention and the electronic water pump using it, through the cooperation of the snap and the latch, force the stator assembly to apply force to the axial limiting step, thereby fixing the stator assembly axially in the stator chamber of the pump housing; and, through the cooperation of the potting groove and the cured encapsulating adhesive, the stator assembly is axially and / or radially fixed in the stator chamber of the pump housing; the above-mentioned method provides a reasonable, reliable, stable and durable stator assembly fixing structure for the electronic water pump, which can ensure that the stator assembly will not undergo radial movement, and solve a series of problems such as the instability of the rotating magnetic field, the damage to the drive circuit board caused by the stator assembly movement, and the high operating noise. Attached Figure Description

[0019] Figure 1 This is a perspective view of the electronic water pump in this invention.

[0020] Figure 2 This is an exploded structural view of the electronic water pump in this invention.

[0021] Figure 3This is a cross-sectional view of the electronic water pump in this invention.

[0022] Figure 4 for Figure 3 A magnified view of part A in the image.

[0023] Figure 5 for Figure 3 A magnified view of part B in the image.

[0024] Figure 6 This is a structural view of the stator assembly in this invention.

[0025] The attached diagram is labeled as follows: 1. Pump casing; 11. Rotor chamber; 12. Inner wall portion; 13. Stator chamber; 14. Outer wall portion; 141. Snap-in position; 142. Glue filling groove; 15. Axial limiting step; 16. Shaft core seat; 2. Stator assembly; 21. Stator bracket; 211. Snap-in; 22. Coil; 23. Terminal; 3. Rotor assembly; 31. Rotor bracket; 32. Magnetic ring; 33. Bearing; 34. Impeller body; 4. Shaft core; 5. Pump cover; 51. Inlet; 52. Outlet; 53. Shaft core bracket; 6. Drive circuit board; 7. End cover. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Please see Figures 1-6 This embodiment provides a stator assembly 2 fixing structure, which is applied to an electronic water pump. The electronic water pump includes at least a pump housing 1 and a stator assembly 2.

[0028] The pump housing 1 is a metal housing formed by die casting or machining, or an engineering plastic housing formed by injection molding. In this embodiment, the outer contour of the pump housing 1 is roughly cylindrical, and the stator assembly 2 is used to provide a rotating magnetic field for the stator assembly 2 of the electronic water pump.

[0029] The pump casing 1 forms a rotor chamber 11 and a stator chamber 13 from the inside out. In fact, the rotor chamber 11 is cylindrical and the stator chamber 13 is annular. The two are coaxially arranged and isolated from each other, so that the water flowing through the rotor chamber 11 cannot enter the stator chamber 13.

[0030] In order to axially fix the stator assembly 2 in the stator chamber 13 of the pump casing 1, the following describes two technical solutions provided in this embodiment.

[0031] Solution 1:

[0032] The pump casing 1 forms an axial limiting step 15 in the stator chamber 13. In this embodiment, the axial limiting step 15 is integrally formed with the pump casing 1 and protrudes in an annular shape in the stator chamber 13 of the pump casing 1, thereby forming the shape of a step.

[0033] The stator assembly 2 and the stator chamber 13 of the pump housing 1 are provided with: one of them is provided with a buckle 211, and the other is provided with a latch 141 that matches the shape of the buckle 211.

[0034] After the stator assembly 2 is installed into the stator chamber 13 of the pump housing 1, at least a portion of the stator assembly 2 abuts against the axial limiting step 15, and the latch 211 and the latch 141 cooperate with each other to force the stator assembly 2 to exert force on the axial limiting step 15, thereby axially fixing the stator assembly 2 in the stator chamber 13 of the pump housing 1.

[0035] The second technical solution:

[0036] The stator assembly 2 and the stator chamber 13 of the pump housing 1 are further provided with at least one of them having a glue filling slot 142;

[0037] After the stator assembly 2 is installed into the stator chamber 13 of the pump housing 1, encapsulating adhesive is poured into the stator chamber 13 of the pump housing 1. The liquid encapsulating adhesive can fill the potting groove 142. The cured encapsulating adhesive can fix the stator assembly 2 axially and / or radially in the stator chamber 13 of the pump housing 1.

[0038] In fact, one or more glue-filling slots 142 can be provided in the stator chamber 13 of the pump housing 1, such as four in this embodiment, or one to three in other embodiments, or more.

[0039] It should be noted that the encapsulant is a commonly used encapsulant in the prior art for encapsulating electronic or electrical products, such as epoxy encapsulants, silicone encapsulants, polyurethane encapsulants, and UV-curable encapsulants.

[0040] It is understood that the two technical solutions mentioned above can be applied independently to the same specific product, or they can be applied in parallel to a specific product. That is, a specific product can have either the first technical solution or the second technical solution, or both of the first and second technical solutions can coexist, both of which can enable the stator assembly 2 to achieve a good axial fixing effect.

[0041] Specifically, the stator assembly 2 is provided with a snap fastener 211, and the stator chamber 13 of the pump housing 1 is provided with a snap position 141 that matches the snap fastener 211. In fact, one or more snap fasteners 211 can be provided on the stator assembly 2, such as four in this embodiment, or one to three in other embodiments, or more. Correspondingly, snap positions 141 corresponding to the number of snap fasteners 211 need to be provided in the stator chamber 13 of the pump housing 1, and the circumferential position of each snap position 141 should correspond to each snap fastener 211 on the stator assembly 2.

[0042] More specifically, the stator assembly 2 includes a stator support 21 and a coil 22 wound on the stator support 21. The stator support 21 is a support made of metal or engineering plastic and is used to provide a structural support base for the stator assembly 2. The coil 22 is formed by winding enameled copper wire a certain number of turns. At least a portion of the stator support 21 extends to form a buckle 211, that is, the buckle 211 is integrally formed with the stator support 21. In this embodiment, all the buckles 211 extend in the same direction.

[0043] Specifically, the pump casing 1 is provided with an inner wall portion 12 and an outer wall portion 14 from the inside out. The inner wall portion 12 and the outer wall portion 14 are both partition walls on the pump casing 1, and the outer wall portion 14 constitutes the outer wall of the pump casing 1. The cavity inside the inner wall portion 12 is the rotor chamber 11, and the cavity between the inner wall portion 12 and the outer wall portion 14 is the stator chamber 13. The axial limiting step 15 is provided on the inner wall of the outer wall portion 14 or the outer wall of the inner wall portion 12. The latch 141 is provided on the inner wall of the outer wall portion 14 or the outer wall of the inner wall portion 12. The glue filling groove 142 is also provided on the inner wall of the outer wall portion 14 or the outer wall of the inner wall portion 12. In this embodiment, the axial limiting step 15, the latch 141, and the glue filling groove 142 are all provided on the inner wall of the outer wall portion 14.

[0044] This embodiment also provides an electronic water pump, which includes the aforementioned stator assembly 2 fixing structure.

[0045] Specifically, the electronic water pump in this embodiment also includes a rotor assembly 2, a shaft core 4, a pump cover 5, a drive circuit board 6, and an end cover 7.

[0046] Among them, the shaft core 4 is a cylindrical shaft made of metal, used to support the rotor assembly 2; the pump cover 5 is a metal cover formed by die casting or machining, or an engineering plastic cover formed by injection molding; the drive circuit board 6 is based on a printed circuit board, and the drive circuit board 6 is equipped with the main controller and power electronic devices and their peripheral circuits for driving the stator assembly 2; the end cover 7 is a metal cover formed by die casting or machining.

[0047] Specifically, the rotor assembly 2 includes a rotor support 31, a magnetic ring 32, a bearing 33, and an impeller body 34. The rotor support 31 is an integrally injection-molded engineering plastic support, the magnetic ring 32 is magnetic, the bearing 33 is a graphite bearing or a ceramic bearing, and the impeller body 34 has several blades made of the same material as the rotor support 31. The magnetic ring 32 is fitted on the outside of the rotor support 31, and the bearing 33 is inserted on the inside of the rotor support 31. The rotor support 31, the magnetic ring 32, and the bearing 33 are usually integrated by in-mold injection molding, and the impeller body 34 is fixed to one end of the rotor support 31 by ultrasonic welding.

[0048] The pump cover 5 has an inlet 51 and an outlet 52 extending through its inner and outer sides, forming inlet and outlet channels. A shaft support 53 is provided inside the pump cover 5, and a shaft seat 16 is provided inside the rotor chamber 11 of the pump casing 1. Both the shaft support 53 and the shaft seat 16 are adapted to allow one end of the shaft 4 to be inserted into them. The pump cover 5 closes onto one end of the pump casing 1 (specifically, the open end of the rotor chamber 11), forming a cavity structure inside the pump cover 5, called a chamber. At this time, the shaft of the pump cover 5... The core support 53 and the core seat 16 of the pump casing 1 are aligned with each other; the core 4 spans between the rotor chamber 11 and the cavity, and the two ends of the core 4 are respectively inserted into the core support 53 of the pump cover 5 and the core seat 16 of the pump casing 1; the rotor assembly 2 is rotatably connected to the core 4, specifically, the bearing 33 of the rotor assembly 2 is sleeved on the core 4, so that the entire rotor assembly 2 can rotate around the core 4; after assembly, the impeller body 34 is located in the cavity, and the stator assembly 2 surrounds the magnetic ring 32 of the rotor assembly 2.

[0049] The drive circuit board 6 is fixed in the pump housing 1 and located on the end face of the stator chamber 13. The drive circuit board 6 can be fixed to the pump housing 1 by means of clips or screws. A rigid terminal 23 is inserted into the stator bracket 21 of the stator assembly 2. One end of the terminal 23 is electrically connected to the coil 22, and the other end is soldered to the drive circuit board 6 to complete the electrical connection between the drive circuit board 6 and the stator assembly 2.

[0050] The end cover 7 is placed on the other end of the pump housing 1 (specifically the open end of the stator chamber 13) and covers the drive circuit board 6 and the stator assembly 2 to seal the drive circuit board 6 and the stator assembly 2. If the end cover 7 and the drive circuit board 6 are attached to each other, or if a heat-conducting medium is provided between them, the end cover 7 can also be used to dissipate heat from the drive circuit board 6.

[0051] In this embodiment, the electronic water pump supplies power to the drive circuit board 6, which drives the stator assembly 2 to operate, generating a rotating magnetic field in the inner cavity of the stator assembly 2. This rotating magnetic field can magnetically couple and drive the entire rotor assembly 2 to rotate. The impeller body 34 rotating in the cavity can drive the water flow in the cavity, forming a certain negative pressure. Water from outside the electronic water pump can be drawn into the cavity from the inlet 51 and discharged from the outlet 52, thus realizing the function of driving the water flow in a directional manner.

[0052] The stator assembly 2 fixing structure and the electronic water pump using it in this embodiment, through the cooperation of the buckle 211 and the latch 141, force the stator assembly 2 to apply force to the axial limiting step 15, thereby axially fixing the stator assembly 2 in the stator chamber 13 of the pump housing 1; and, through the cooperation of the potting groove 142 and the cured encapsulating adhesive, the stator assembly 2 is axially and / or radially fixed in the stator chamber 13 of the pump housing 1. The above-mentioned method provides a reasonable, reliable, stable and durable stator assembly 2 fixing structure for the electronic water pump, which can ensure that the stator assembly 2 will not move radially, and solve a series of problems such as the instability of the rotating magnetic field, the damage to the drive circuit board 6 caused by the movement of the stator assembly 2, and the high operating noise.

[0053] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A stator assembly fixing structure, applied in an electronic water pump, wherein the electronic water pump includes at least a pump housing and a stator assembly; characterized in that, The pump casing is formed from the inside out as a rotor chamber and a stator chamber; The pump casing forms an axial limiting step within the stator chamber; The stator assembly is provided with a snap fastener, and the stator chamber of the pump housing is provided with a snap position that matches the snap fastener; After the stator assembly is installed into the stator chamber of the pump housing, at least a portion of the stator assembly abuts against the axial limiting step, and the latch and the latching position cooperate with each other to force the stator assembly to exert force on the axial limiting step, thereby axially fixing the stator assembly in the stator chamber of the pump housing. The stator assembly and the stator chamber of the pump housing further include: at least one of them being provided with a glue-filling groove; After the stator assembly is installed into the stator chamber of the pump housing, encapsulating adhesive is poured into the stator chamber of the pump housing. The liquid encapsulating adhesive can fill the filling groove, and the cured encapsulating adhesive can fix the stator assembly axially and / or radially in the stator chamber of the pump housing.

2. The stator assembly fixing structure according to claim 1, characterized in that, The stator assembly includes a stator support and coils wound on the stator support; At least a portion of the stator support extends to form the latch.

3. The stator assembly fixing structure according to claim 1, characterized in that, The pump casing is provided with an inner wall portion and an outer wall portion from the inside out; The cavity inside the inner wall portion is the rotor chamber, and the cavity between the inner wall portion and the outer wall portion is the stator chamber. The axial limiting step is disposed on the inner wall of the outer wall portion or on the outer wall of the inner wall portion; The fastener is formed on the inner wall of the outer wall portion or on the outer wall of the inner wall portion; The glue-filling groove is also provided on the inner wall of the outer wall portion or on the outer wall of the inner wall portion.

4. An electronic water pump, characterized in that, It includes the stator assembly fixing structure as described in any one of claims 1-3.

Images