Electric pump and electric pump assembling method

Abstract

An electric pump. The electric pump comprises a rotor assembly, a pump shaft, a shaft limiting portion and an isolation sleeve, wherein the rotor assembly is located on the periphery of the pump shaft, and the pump shaft is fixedly connected to or limitingly connected to the shaft limiting portion; the shaft limiting portion comprises a first welding part, the isolation sleeve comprises a bottom portion, the bottom portion comprises a second welding part, and the first welding part and the second welding part are fixed by means of welding; the bottom portion has a first end face and a second end face, and in an axial direction parallel to the electric pump, the first end face is close to the shaft limiting portion relative to the second end face; the area of the projection of the second welding part on the first end face is smaller than the area of the projection of the shaft limiting portion on the first end face, and a distance is present between the second welding part and the second end face. The present application further discloses an electric pump assembling method. The present application has the characteristic of reducing the leakage risk.

Description

Electric pump and electric pump assembly method

[0001] This application claims priority to the following three Chinese patent applications, the entire contents of which are incorporated herein by reference:

[0002] 1. Submitted to the China Patent Office on August 31, 2023, application number 202322366995.0, invention name “Electric Pump”;

[0003] 2. Submitted to the China Patent Office on July 28, 2023, application number 202322018081.5, invention name “An Electric Pump”;

[0004] 3. Submitted to the China Patent Office on August 25, 2023, application number 202311084501.8, invention name “An electric pump and an assembly method of an electric pump”;

Technical field

[0005] The present application relates to the field of vehicles, and in particular to components of a vehicle lubrication system and / or cooling system. [Background Technology]

[0006] Electric pumps include a spacer sleeve, which isolates the stator and rotor assemblies, preventing contact between the working medium and the stator assembly during operation. The electric pump also includes a shaft retainer, to which the spacer sleeve is welded. Due to the thin wall thickness of the spacer sleeve, high welding energy can easily damage it, posing a risk of leakage in the electric pump. Therefore, mitigating this risk is a technical challenge.

[0007] [Summary of the invention]

[0008] The purpose of this application is to provide an electric pump that helps reduce the risk of leakage.

[0009] To achieve the above objectives, one embodiment of the present application adopts the following technical solution:

[0010] An electric pump comprises a rotor assembly, a pump shaft, a shaft limiting portion and an isolation sleeve, wherein the rotor assembly is located on the outer periphery of the pump shaft, the pump shaft is fixedly connected or limitedly connected to the shaft limiting portion, the shaft limiting portion comprises a first welding portion, the isolation sleeve comprises a bottom, the bottom comprises a second welding portion, the first welding portion is welded and fixed to the second welding portion, the bottom has a first end face and a second end face, along a direction parallel to the axial direction of the electric pump, the first end face is close to the shaft limiting portion relative to the second end face, the area of ​​the projection of the second welding portion on the first end face is smaller than the area of ​​the projection of the shaft limiting portion on the first end face, and there is a distance between the second welding portion and the second end face.

[0011] In the above technical solution, along the direction parallel to the axial direction of the electric pump, the area of ​​the projection of the second welding part on the first end face is smaller than the area of ​​the projection of the shaft limiting part on the first end face, and there is a distance between the second welding part and the second end face. When the isolation sleeve is fixedly connected to the shaft limiting part, the contact area between the bottom and the shaft limiting part is small, and the energy required for welding is small. Along the direction parallel to the axial direction of the electric pump, at least part of the bottom is not melted, so that at least part of the bottom is not damaged, which is beneficial to reduce the risk of leakage.

[0012] One embodiment of the present application further discloses the following technical solution: an assembly method of an electric pump, the assembly method of the electric pump comprising:

[0013] Obtain the shaft limiter and isolation sleeve;

[0014] The shaft limiting portion and the isolation sleeve are fixedly connected: a first welding portion of the shaft limiting portion and a second welding portion of the isolation sleeve are fixed by welding, and during welding, a portion of the bottom of the isolation sleeve is melted in a direction parallel to the axial direction of the electric pump.

[0015] In the above technical solution, when welding the first welding part of the fixed shaft limit part and the second welding part of the isolation sleeve, part of the bottom of the isolation sleeve is melted along the direction parallel to the axial direction of the electric pump, so that at least part of the bottom is not damaged, which is beneficial to reduce the risk of leakage.

Brief Description of the Drawings

[0016] FIG1 is a schematic diagram of an electric pump according to an embodiment of the present application;

[0017] FIG2 is a schematic cross-sectional view of the electric pump shown in FIG1 ;

[0018] FIG3 is a schematic diagram of the first perspective of the isolation sleeve, the pump shaft and the shaft limiting portion in FIG2 being fixed;

[0019] FIG4 is a schematic diagram of a second perspective of the isolation sleeve, the pump shaft and the shaft limiting portion in FIG2 being fixed;

[0020] FIG5 is a schematic diagram of a first embodiment of the AA section in FIG4 ;

[0021] FIG6 is an enlarged schematic diagram of portion A in FIG5 ;

[0022] FIG7 is a schematic diagram of the shaft limiting portion shown in FIG5 from a first viewing angle;

[0023] FIG8 is a schematic cross-sectional view of the shaft limiting portion shown in FIG7 ;

[0024] FIG9 is a schematic diagram of the first embodiment of the shaft limiting portion shown in FIG5 from a different perspective;

[0025] FIG10 is a schematic diagram of a second embodiment of the shaft limiting portion shown in FIG5 from a different perspective;

[0026] FIG11 is a schematic diagram of a second embodiment of the AA section in FIG4 ;

[0027] FIG12 is an enlarged schematic diagram of portion A in FIG11 ;

[0028] FIG13 is a schematic diagram of the isolation sleeve in FIG4;

[0029] FIG14 is a schematic diagram of the first embodiment of the isolation sleeve shown in FIG13 from a different perspective;

[0030] FIG15 is a schematic diagram of a second embodiment of the isolation sleeve shown in FIG13 from a different perspective;

[0031] FIG16 is a schematic diagram of an electric pump according to an embodiment of the present application;

[0032] FIG17 is a schematic cross-sectional view of the electric pump shown in FIG16 ;

[0033] FIG18 is a schematic diagram of the first perspective of the isolation sleeve, the pump shaft and the shaft stopper in FIG17;

[0034] FIG19 is a schematic diagram of the second perspective of the isolation sleeve, the pump shaft and the shaft stopper in FIG17;

[0035] FIG20 is a schematic diagram of the AA section in FIG19;

[0036] FIG21 is a schematic diagram of the shaft limiting portion shown in FIG18 from a first viewing angle;

[0037] FIG22 is a schematic diagram of the shaft limiting portion shown in FIG18 from a second viewing angle;

[0038] FIG23 is a schematic cross-sectional view of the shaft limiting portion shown in FIG22 ;

[0039] FIG24 is a schematic diagram of another embodiment of fixing the isolation sleeve, the pump shaft and the shaft stopper;

[0040] FIG25 is a schematic diagram of the fixing of the shaft limiting portion and the pump shaft in FIG24;

[0041] FIG26 is a schematic diagram of another embodiment of fixing the isolation sleeve, the pump shaft and the shaft stopper;

[0042] FIG27 is a cross-sectional schematic diagram of an embodiment of a shaft limiting portion;

[0043] FIG28 is a cross-sectional schematic diagram of an embodiment of a shaft limiting portion;

[0044] FIG29 is a cross-sectional schematic diagram of an embodiment of a shaft limiting portion;

[0045] FIG30 is a cross-sectional schematic diagram of an embodiment of a shaft limiting portion;

[0046] FIG31 is a schematic perspective view of the first embodiment of the electric pump of the present application;

[0047] FIG32 is a schematic cross-sectional view of the first embodiment of the electric pump in FIG31 along XX;

[0048] FIG33 is a schematic diagram of the three-dimensional structure of the shaft sleeve in one direction in the first embodiment of the electric pump in FIG32 ;

[0049] FIG34 is a schematic cross-sectional view of the second embodiment of the electric pump in FIG31 along XX;

[0050] FIG35 is a schematic cross-sectional view of the third embodiment of the electric pump in FIG31 along the line XX;

[0051] FIG36 is a schematic cross-sectional view of the fourth embodiment of the electric pump in FIG31 along XX;

[0052] FIG37 is a schematic cross-sectional view of the fifth embodiment of the electric pump in FIG31 along line XX;

[0053] FIG38 is a schematic diagram of the cross-sectional structure of the electric pump embodiment along line YY in FIG32;

[0054] FIG39 is an enlarged structural diagram of point I in FIG38;

[0055] Reference numerals: 1, pump housing; 111, pump housing; 1111, inlet; 1112, outlet; 1113, support portion; 1114, bypass channel; 112, motor housing; 113, bottom cover; 2, stator assembly; 3, isolation sleeve; 32, bottom; 321, first end surface; 3211, first inner end surface; 3212, first outer end surface; 322, second end surface; 30, isolation cavity; 12, rotating assembly; 41, permanent magnet; 121, rotor assembly; 1211, rotor portion; 1212, Injection molding part; 1212a, first part; 1212b, second part; 122, impeller assembly; 1221, inflow channel; 123, bushing; 1231, first bushing; 1231a, upper wall; 1232, second bushing; 1232a, lower wall; 124, limiting hole; 1241, wall corresponding to the limiting hole; 31, bottom wall; 311, first sub-bottom wall; 312, second sub-bottom wall; 5, pump shaft; 51, first sub-section; 52, second sub-section; 53, third sub-section; 151, shaft hole; 152, horizontal hole; 153, upper end; 154, lower end; 155, outer wall; 156, vertical hole; 157, horizontal groove; 6, control assembly; 141, substrate; 142, electronic components; 7. Shaft stopper; 70. Accommodating cavity; 71. Fixing portion; 72. Base; 721. Third end surface; 7211. Third inner end surface; 7212. Third outer end surface; 722. Bottom portion; 73. Connecting portion; 75. Circulation hole; 731. First circulation hole; 732. Second circulation hole; 74. Connecting portion; 741. First connecting subsection; 742. Second connecting subsection; 8. Welding portion; 81. First welding portion; 811. First welding protrusion; 82. Second welding portion; 821. Second welding protrusion; 10. First cavity; 20. Second cavity; 18. Return channel; 181. Flow channel; 1811. First flow channel; 1812. Second flow channel; 1813. Wall corresponding to the flow channel; 182. Internal flow channel; 19. Water channel; 20. Rotor cavity; 201. Bottom; 21. Insertion pin; 22. Pump cavity; 2211. Rotor cavity; 2212. Impeller cavity [Specific implementation method]

[0056] The present application will be further described below with reference to the accompanying drawings and specific embodiments:

[0057] In order to enable those skilled in the art to better understand the technical solution of the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without paying any creative work. The directional words such as upper and lower involved in this article are defined by the positions of the parts relative to each other shown in the drawings. They are only for the clarity and convenience of expressing the technical solution. It should be understood that the directional words used in this article should not limit the scope of protection requested by this application.

[0058] The electric pump of this application can be applied to a liquid circulation system. The electric pump can drive the flow of liquid in the circulation system. The fluid can be lubricating oil in a lubrication system or coolant in a cooling system. This application takes the electric pump applied to a cooling circulation system as an example.

[0059] Referring to Figures 1 to 15 , the electric pump includes a pump housing 1, a stator assembly 2, a spacer sleeve 3, a rotating assembly 12, a pump shaft 5, and a control assembly 6. The pump housing 1 forms a pump interior cavity, which includes a first chamber 10 and a second chamber 20. The first chamber 10 and the second chamber 20 are not connected. During operation, a working medium flows through the first chamber 10, while the second chamber 20 is not directly exposed to the working medium. The rotating assembly 12 and at least a portion of the pump shaft 5 are located in the first chamber 10, while at least a portion of the stator assembly 2 and at least a portion of the control assembly 6 are located in the second chamber 20. The stator assembly 2 and the control assembly 6 are not in contact with the working medium, thereby preventing short circuits. The rotating assembly 12 is sleeved around the outer periphery of the pump shaft 5. The stator assembly 2 is electrically connected to the control assembly 6. The rotating assembly 12 includes a permanent magnet 41 and an impeller assembly 42. During operation, the control assembly 6 controls the current flowing through the stator assembly 2, thereby controlling the excitation magnetic field generated by the stator assembly 2. Under the influence of the excitation magnetic field, the rotating assembly 12 rotates around or along the pump shaft 5.

[0060] Please refer to Figures 5 to 15. The electric pump also includes a shaft limiting portion 7, which is fixedly connected or limitedly connected to the pump shaft 5. The shaft limiting portion 7 includes a first welding portion 81, and the isolation sleeve 3 includes a bottom 32. The bottom 32 includes a second welding portion 82. The first welding portion 81 is welded and fixed to the second welding portion 82. The bottom 32 has a first end face 321 and a second end face 322. Along the direction parallel to the axial direction of the electric pump, the first end face 321 is close to the shaft limiting portion 7 relative to the second end face 322. The area of ​​the projection of the second welding portion 82 on the first end face 321 is smaller than the area of ​​the projection of the shaft limiting portion 7 on the first end face 321. There is a distance between the second welding portion 82 and the second end face 322. When the isolation sleeve 3 is welded to the shaft limiting portion 7, the contact area between the bottom 32 and the shaft limiting portion 7 is small, and the energy required for welding is small. Along the direction parallel to the axial direction of the electric pump, there is a distance between the second welding portion 82 and the second end face 322, and at least part of the bottom 32 is not melted, so that at least part of the bottom 32 is not damaged, which is conducive to reducing the risk of leakage. In this embodiment, the projection of the second welding portion 82 on the first end face 321 overlaps with the projection of the shaft limiting portion 7 on the first end face 321. The welding method of the shaft limiting portion 7 and the isolation sleeve 3 includes but is not limited to resistance welding, friction welding or hot melt welding. The electric pump includes a welding portion 8, and the shaft limiting portion 7 and the isolation sleeve 3 are fixedly connected by the welding portion 8. The welding portion 8 is a melted product when the shaft limiting portion 7 and the isolation sleeve 3 are welded. The welding portion 8 includes a first welding portion 81 and a second welding portion 82.

[0061] The shaft stopper 7 can be a stamped part or a machined part. Furthermore, the shaft stopper 7 is a thin-walled stamped part, which has relatively high production efficiency and relatively low cost. The isolation sleeve 3 can be a stamped part or a machined part. Furthermore, the isolation sleeve 3 is a thin-walled stamped part, which has relatively high production efficiency and relatively low cost.

[0062] The material of the isolation sleeve 3 and the material of the shaft stopper 7 are the same material, for example, both the isolation sleeve 3 and the shaft stopper 7 are made of metal. Furthermore, the material of the isolation sleeve 3 and the shaft stopper 7 are both stainless steel. Stainless steel has a high hardness and is not prone to rusting after long-term contact with the working medium (such as water). It can effectively protect the components installed in the isolation chamber 30 without affecting the water quality. In addition, it will not crack or age after long-term use and has a high compressive strength.

[0063] In one embodiment, please refer to Figures 5 to 10, the shaft limiting portion 7 has a third end face 721, the extension direction of the first end face 321 is parallel to the extension direction of the third end face 721, the first welding portion 81 extends from the third end face 721 in a direction away from the shaft limiting portion 7, and the first welding portion 81 does not extend to the second end face 322. When the isolation sleeve 3 is welded to the shaft limiting portion 7, at least part of the bottom 32 is not melted along a direction parallel to the axial direction of the electric pump, so that at least part of the bottom 32 is not damaged, which is beneficial to reduce the risk of leakage.

[0064] Along the direction parallel to the axial direction of the electric pump, the first welding portion 81 has a first distance, where the first distance can be understood as the height value of the first welding portion 81 along the axial direction. The distance from the first end face 321 to the second end face 322 is a second distance, where the second distance can be understood as the thickness value along the axial direction from the first end face 321 to the second end face. The ratio of the first distance to the second distance is 0.6 to 2. If the ratio of the first distance to the second distance is greater than 2, since a large amount of energy is required to melt the first welding portion 81, the isolation sleeve 3 may be penetrated when welding the isolation sleeve 3 to the shaft limit portion 7, resulting in a risk of leakage of the isolation sleeve 3. If the ratio of the first distance to the second distance is less than 0.6, since a small amount of energy can melt the first welding portion 81, the fixing strength between the shaft limit portion 7 and the isolation sleeve 3 may be weak, and the reinforcing effect of the isolation sleeve 3 on the bottom 32 of the isolation sleeve 3 after welding the isolation sleeve 3 to the shaft limit portion 7 is weak, and the isolation sleeve 3 is easily deformed by force. In the radial direction of the electric pump, the width of the first welding portion 81 is 0.5 mm to 2 mm. When the shaft limiting portion 7 is welded to the isolation sleeve 3, the first welding portion 81 and the first end face 321 can have a better contact area, thereby making the connection strength between the shaft limiting portion 7 and the isolation sleeve 3 higher.

[0065] In one embodiment, please refer to Figures 5, 9 and 10. Along the direction parallel to the axial direction of the electric pump, the area of ​​the projection of the first welding portion 81 on the third end face 721 is smaller than the area of ​​the third end face 721. The first welding portion 81 includes a plurality of first welding protrusions 811. The first welding protrusions 811 protrude from the third end face 721 in a direction away from the shaft limiting portion 7. The projection of the first welding protrusions 811 on the third end face 721 is circular or polygonal, or the line connecting the projections of the first welding protrusions 811 on the third end face 721 is circular or polygonal. When the isolation sleeve 3 is welded to the shaft limiting portion 7, energy can be concentrated on the first welding protrusions 811. Smaller energy can be used to weld the isolation sleeve 3 to the shaft limiting portion 7. In addition, the welding time is short and the production efficiency is high. Moreover, the connection strength between the isolation sleeve 3 and the shaft limiting portion 7 is relatively high. In other embodiments, the projection of the first welding portion 81 on the third end face 721 is circular or polygonal. In one embodiment, the third end face 721 includes a third inner end face 7211 and a third outer end face 7212, and the first welding portion 81 extends from the third end face 721 in a direction away from the shaft limiting portion 7. Along the radial direction of the shaft limiting portion 7, the third outer end face 7212 is located radially outside the third inner end face 7211, and the first welding portion 81 is located between the third inner end face 7211 and the third outer end face 7212. The projected area of ​​the first welding portion 81 on the third end face 721 is smaller than the area of ​​the third outer end face 7212. When the isolation sleeve 3 is welded to the shaft limiting portion 7, energy can be concentrated on the first welding portion 81, and the fixing strength of the isolation sleeve 3 and the shaft limiting portion 7 is higher. In addition, compared with the welding of the third end face 721 and the first end face 321, the energy requirement is smaller. Along a direction parallel to the axial direction of the electric pump, the projection area of ​​the first welding portion 81 onto the first end surface 321 is smaller than the area of ​​the first end surface 321. This arrangement ensures a large contact area between the first welding portion 81 and the first end surface 321, thereby improving weld strength. Alternatively, the area of ​​the first end surface 321 of the base 32 is defined as the first area, and the projection area of ​​the first welding portion 81 onto the first end surface 321 is defined as the second area, with the first area being larger than the second area. This arrangement ensures a large contact area between the first welding portion 81 and the first end surface 321, thereby improving weld strength.

[0066] In one embodiment, referring to Figures 11 to 15 , the shaft stopper 7 has a third end surface 721. The first end surface 321 extends in a direction parallel to the direction of extension of the third end surface 721. The second welding portion 82 extends from the first end surface 321 in a direction away from the second end surface 322. When the isolation sleeve 3 is welded to the shaft stopper 7, at least a portion of the bottom 32 is not melted in a direction parallel to the axial direction of the electric pump, thereby at least partially undamaged, which helps reduce the risk of leakage.

[0067] The shaft limiting portion 7 includes a base 72, which has a third end face 721. Along the direction parallel to the axial direction of the electric pump, the thickness of the second welding portion 82 is less than the thickness of the base 72. Furthermore, along the direction parallel to the axial direction of the electric pump, the thickness of the second welding portion 82 is 0.3 to 0.7 times the thickness of the base 72. On the one hand, this is conducive to a stronger connection strength between the shaft limiting portion 7 and the isolation sleeve 3; on the other hand, when the isolation sleeve 3 is welded to the shaft limiting portion 7, the energy demand is moderate, which is conducive to energy saving.

[0068] In one embodiment, please refer to Figures 11, 14 and 15. Along the direction parallel to the axial direction of the electric pump, the area of ​​the projection of the second welding portion 82 on the first end surface 321 is smaller than the area of ​​the first end surface 321. The second welding portion 82 includes a plurality of second welding protrusions 821. The second welding protrusions 821 protrude from the first end surface 321 toward away from the bottom 32. The projection of the second welding protrusions 821 on the first end surface 321 is circular or polygonal; or the connecting line of the projections of the second welding protrusions 821 on the first end surface 321 is circular or polygonal. When the isolation sleeve 3 is welded to the shaft limiting portion 7, energy can be concentrated on the second welding protrusions 821. Smaller energy can achieve welding of the isolation sleeve 3 and the shaft limiting portion 7. In addition, the welding time is short and the production efficiency is high. Moreover, the connection strength between the isolation sleeve 3 and the shaft limiting portion 7 is relatively high. In other embodiments, the projection of the second welding portion 82 on the first end surface 321 is circular or polygonal. In one embodiment, please refer to Figure 15, the first end face 321 includes a first inner end face 3211 and a first outer end face 3212, and the second welding portion 82 extends from the first end face 321 in a direction away from the shaft limiting portion 7. In the radial direction of the shaft limiting portion 7, the first outer end face 3212 is located radially outside the first inner end face 3211, and the second welding portion 82 is located between the first inner end face 3211 and the first outer end face 3212. The projected area of ​​the second welding portion 82 on the first end face 321 is smaller than the area of ​​the first outer end face 3212. When the isolation sleeve 3 is welded to the shaft limiting portion 7, energy can be concentrated on the second welding portion 82, and the fixing strength of the isolation sleeve 3 and the shaft limiting portion 7 is higher. In addition, compared with the welding of the third end face 721 and the first end face 321, the energy requirement is smaller. Along a direction parallel to the axial direction of the electric pump, the projection area of ​​the second welding portion 82 on the third end surface 721 is smaller than the area of ​​the third end surface 721. This arrangement ensures a large contact area between the second welding portion 82 and the third end surface 721, thereby improving weld strength. Alternatively, the area of ​​the third end surface 721 of the shaft stop 7 is defined as a first area, and the projection area of ​​the second welding portion 82 on the third end surface 721 is defined as a second area, with the first area being larger than the second area. This arrangement ensures a large contact area between the second welding portion 82 and the third end surface 721, thereby improving weld strength.

[0069] Referring to Figures 2 to 15 , the shaft retaining portion 7 covers a portion of the first end surface 321. The shaft retaining portion 7 includes a base 72, which includes a third end surface 721. Along a direction parallel to the axial direction of the electric pump, the thickness of the isolation sleeve 3 is less than the thickness of the base 72. Furthermore, the thickness of the bottom 32 is less than the thickness of the base 72. Because the bottom 32 is closer to the control assembly 6 relative to the base 72 along the axial direction of the electric pump, heat generated by the control assembly 6 is transferred to the bottom 32. Since the bottom 32 is relatively thin and has a relatively high heat conduction rate, the heat can be quickly transferred to the shaft retaining portion 7. The outer surface of the shaft retaining portion 7 is in contact with the working medium, which helps improve the heat dissipation effect of the electric pump. For example, when the bottom 32 and the base 72 are made of the same stainless steel, the bottom 32 is thinner and has a relatively high thermal conductivity. The bottom 32 can quickly transfer heat to the shaft retaining portion 7 (or base 72), while the outer surface and at least a portion of the inner surface of the shaft retaining portion 7 are in contact with the working medium, which helps improve the heat dissipation effect of the electric pump. In the radial direction of the electric pump, the width of the bottom 32 (or the first end surface 321) is defined as a first width W1, and the maximum width of the shaft stopper 7 is defined as a second width W2, wherein the first width is greater than the second width; further, the second width is 0.5 to 0.9 times the first width, for example, if the first width is 30 mm, the second width ranges from 15 mm to 27 mm; further, the second width is 0.6 to 0.8 times the first width. This allows the bottom 32 to have a larger contact area with the shaft stopper 7, which is beneficial for improving the connection strength between the shaft stopper 7 and the isolation sleeve 3. After the shaft stopper 7 is fixed to the isolation sleeve 3, the thickness of the bottom 32 is increased, which is beneficial for increasing the deformation resistance of the bottom 32 of the isolation sleeve 3, making the isolation sleeve 3 less susceptible to deformation under stress.

[0070] In this embodiment, please refer to Figures 5 to 15. The shaft limiting portion 7 includes a fixing portion 71, a connecting portion 73 and a base 72. The connecting portion 73 is connected to the fixing portion 71, and the connecting portion 73 is connected to the base 72. The fixing portion 71 is fixedly connected or limitedly connected to the pump shaft 5. The base 72 is welded and fixed to the isolation sleeve 3. The base 72 extends from the connecting portion 73 in a direction away from the pump shaft 5, so that there is a larger contact area between the shaft limiting portion 7 and the isolation sleeve 3. After the shaft limiting portion 7 is fixed to the isolation sleeve 3, it is equivalent to increasing the thickness of part of the bottom 32, which is beneficial to increase the deformation resistance of the bottom 32 of the isolation sleeve 3, so that the isolation sleeve 3 is not easily deformed by force.

[0071] A method for assembling an electric pump, the method comprising:

[0072] Obtain the shaft limiting portion 7 and the isolation sleeve 3;

[0073] Prepare the weld 8: Weld and secure the shaft stopper 7 and the isolation sleeve 3. Specifically, securely connect the shaft stopper 7 and the isolation sleeve 3 by welding a first weld 81 of the shaft stopper 7 and a second weld 82 of the isolation sleeve 3. During welding, a portion of the bottom 32 of the isolation sleeve 3 is melted in a direction parallel to the axial direction of the electric pump, thereby at least partially maintaining the bottom 32 and reducing the risk of leakage.

[0074] The assembly method of the electric pump includes: obtaining the pump shaft 5, fixedly connecting or limiting the connection between the pump shaft 5 and the shaft limiting part 7, and fixing or limiting the connection between the pump shaft 5 and the shaft limiting part 7. This can make the concentricity of the pump shaft 5 and the shaft limiting part 7 higher, and when the electric pump is working, the vibration amplitude of the pump shaft 5 is smaller and the noise is smaller.

[0075] In one embodiment, when preparing the weld 8 or when securely connecting the shaft stop 7 and the isolation sleeve 3, a first welding electrode and a second welding electrode are provided. The first welding electrode contacts the isolation sleeve 3, and the second welding electrode contacts the pump shaft 5. Current is then transferred between the first welding electrode and the second welding electrode. One of the isolation sleeve 3 and the pump shaft 5 is connected to the positive electrode, and the other to the negative electrode. When power is applied, the first and second welds are melted, thereby securing the isolation sleeve 3 to the shaft stop 7. Furthermore, because welding is performed from within the isolation sleeve 3, at least a portion of the isolation sleeve 3 is not damaged, and the risk of leakage from the isolation sleeve 3 is relatively low.

[0076] 5 and 11 , in the axial direction of the electric pump, a gap is provided between the pump shaft 5 and the bottom wall (or first end face 321) of the isolation sleeve 3. That is, the pump shaft 5 does not contact the first end face 321 of the isolation sleeve 3, or there is a certain distance between the pump shaft 5 and the first end face 321 of the isolation sleeve 3. For example, when resistance welding is used to connect the isolation sleeve 3 and the shaft stopper 7, if the pump shaft 5 contacts the isolation sleeve 3, current will flow directly from the pump shaft 5 to the isolation sleeve 3, affecting the fixing effect between the isolation sleeve 3 and the shaft stopper 7. In some embodiments, the shaft stopper 7 has a receiving cavity 70, which is connected to the isolation cavity 30. When the electric pump is operating, the receiving cavity 70 contains working medium, and at least part of the pump shaft 5 is located in the receiving cavity 70. In the axial direction of the electric pump, the distance between the pump shaft 5 and the first end face 321 of the isolation sleeve 3 ranges from 0.2 mm to 2 mm. This ensures the fixing effect between the isolation sleeve 3 and the shaft stopper 7 while allowing the pump shaft 5 to have a larger contact area with the working medium. Of course, in other embodiments, the spacing between the pump shaft 5 and the first end surface 321 of the isolation sleeve 3 ranges from 0.2 mm to 1 mm, ensuring that the isolation sleeve 3 and the shaft stop 7 are secured while also providing a larger contact area between the pump shaft 5 and the working medium. Furthermore, the spacing between the pump shaft 5 and the first end surface 321 of the isolation sleeve 3 ranges from 0.5 mm to 1 mm. This ensures that the isolation sleeve 3 and the shaft stop 7 are secured while also providing a larger contact area between the pump shaft 5 and the working medium.

[0077] Referring to Figures 15 to 30 , the electric pump includes a pump housing 1, a stator assembly 2, a spacer sleeve 3, a rotating assembly 12, a pump shaft 5, and a control assembly 6. The pump housing 1 forms a pump inner cavity, which includes a first cavity 10 and a second cavity 20. The first cavity 10 and the second cavity 20 are not connected. During operation, the working medium flows through the first cavity 10, while the working medium does not flow through the second cavity 20. The rotating assembly 12 and at least a portion of the pump shaft 5 are located in the first cavity 10, while at least a portion of the stator assembly 2 and at least a portion of the control assembly 6 are located in the second cavity 20. In this embodiment, the stator assembly 2 and the control assembly 6 are located in the second cavity 20. The stator assembly 2 and the control assembly 6 are not in contact with the working medium, which helps prevent short circuits. The rotating assembly 12 is located on the periphery of the pump shaft 5. The stator assembly 2 is electrically connected to the control assembly 6. The rotating assembly 12 includes a permanent magnet 41 and an impeller assembly 42. During operation, the control assembly 6 controls the current flowing through the stator assembly 2, thereby controlling the excitation magnetic field generated by the stator assembly 2. The rotating assembly 12 rotates under the influence of the excitation magnetic field. Specifically, the rotating assembly 12 rotates around the pump shaft 5 or along with the pump shaft 5 under the action of the excitation magnetic field.

[0078] The electric pump further includes a shaft stopper 7, which is fixedly connected or position-limitingly connected to the pump shaft 5. The shaft stopper 7 is fixedly connected or position-limitingly connected to the isolation sleeve 3 to achieve fixation of the shaft stopper 7. Specifically, the isolation sleeve 3 has a bottom wall 31, and the shaft stopper 7 is fixedly connected to the bottom wall 31.

[0079] In this embodiment, the isolation sleeve 3 divides the pump cavity into a first cavity 10 and a second cavity 20. The isolation sleeve 3 has an isolation cavity 30. The first cavity 10 includes the isolation cavity 30. The upper end of the isolation cavity 30 is open to facilitate the assembly of the rotating assembly 12. The rotating assembly 12 and at least part of the pump shaft 5 are located in the isolation cavity 30. The shaft limiting portion 7 has a accommodating cavity 70. The isolation sleeve 3 has an isolation cavity 30. The accommodating cavity 70 is connected to the isolation cavity 30. When the electric pump is working, there is a working medium in the isolation cavity 30. The accommodating cavity 70 is connected to the isolation cavity 30. The accommodating cavity 70 can contain a working medium. At least part of the inner wall and at least part of the outer wall of the shaft limiting portion 7 are in contact with the working medium. The surface area of ​​the shaft limiting portion 7 in contact with the working medium is large, which increases the heat dissipation area of ​​the working medium, thereby facilitating the improvement of the heat dissipation effect of the electric pump. In addition, the shaft limiting portion 7 has a accommodating cavity 70. The weight of the shaft limiting portion 7 is relatively light, which helps to reduce the weight of the electric pump.

[0080] The shaft limiting portion 7 has at least one flow hole 75, which communicates with the isolation chamber 30 and the accommodating chamber 70. Referring to Figures 15, 25, and 27 to 29, the shaft limiting portion 7 has at least two flow holes 75. The working medium in the isolation chamber 30 can flow into the accommodating chamber 70 through the at least one flow hole 75, and the working medium in the accommodating chamber 70 can flow out of the accommodating chamber 70 through the at least one flow hole 75. At least a portion of the inner wall and at least a portion of the outer wall of the shaft limiting portion 7 are in contact with the working medium. The surface area of ​​the shaft limiting portion 7 in contact with the working medium is large, which increases the heat dissipation area of ​​the working medium, thereby facilitating improved heat dissipation of the electric pump.

[0081] Please refer to Figures 18 to 25. The shaft limiting portion 7 includes a fixing portion 71, a base 72 and a connecting portion 74. The connecting portion 74 is connected to the fixing portion 71, and the connecting portion 74 is connected to the base 72. The fixing portion 71 is fixedly connected or limit-connected to the pump shaft 5, and the base 72 is fixedly connected or limit-connected to the isolation sleeve 3. The connecting portion 74 has a flow hole 75, which is connected to the isolation chamber 30, and the flow hole 75 is connected to the accommodating chamber 70.

[0082] Referring to Figures 24 and 25 , the isolation sleeve 3 has a bottom wall 31. The connecting portion 74 extends from the fixed portion 71 toward the bottom wall 31. The wall of the accommodating chamber 70 includes the inner wall of the connecting portion 74 and a portion of the bottom wall 31. When the electric pump is operating, a working medium is contained within the isolation chamber 30. The working medium within the isolation chamber 30 can flow into the accommodating chamber 70. The inner wall of the connecting portion 74 and a portion of the bottom wall 31 can contact the working medium. The inner wall of the connecting portion 74 and at least a portion of the outer wall of the shaft stop 7 can also contact the working medium. The surface area of ​​the shaft stop 7 in contact with the working medium is large, increasing the heat dissipation area of ​​the working medium, thereby improving the heat dissipation effect of the electric pump. In one embodiment, the connecting portion 75 has at least two flow holes 75 arranged radially along the connecting portion 74. The flow holes 75 allow the working medium to flow into and out of the accommodating chamber 70 almost simultaneously, resulting in a faster flow rate of the working medium, which improves the heat dissipation effect of the electric pump. In one embodiment, the flow holes 75 are arranged axially along the connecting portion 74. Since some of the flow holes 75 are relatively close to the bottom wall 31 along the direction parallel to the axial direction of the electric pump, the working medium can flow into the accommodating cavity 70 faster, which is beneficial to improving the heat exchange rate between the shaft limiting portion 7 and the working medium.

[0083] Referring to Figures 20 to 23 , the connecting portion 74 includes a first connecting section 741 and a second connecting section 742. The first connecting section 741 connects to the second connecting section 742. The first connecting section 741 extends in a direction parallel to the direction of extension of the fixing portion 71, and the first connecting section 741 extends perpendicular to the direction of extension of the second connecting section 742. The above arrangement includes a rounded corner design at the connection between the first connecting section 741 and the second connecting section 742. The cavity wall of the accommodating chamber 70 includes at least the inner wall of the first connecting section 741 and the inner wall of the second connecting section 742. This arrangement allows the accommodating chamber 70 to have a larger volume, a larger heat dissipation area for the working medium, and is conducive to improving the heat dissipation effect of the electric pump.

[0084] The first connecting section 741 has a flow hole 75. Because the first connecting section 741 is relatively close to the bottom wall 31, the flow hole 75 allows the working medium to flow into the accommodating chamber 70 more quickly, thereby improving the heat exchange rate between the shaft stop 7 and the working medium. In one embodiment, the second connecting section 742 has a flow hole 75. The second connecting section 742 is relatively far from the bottom wall 31, allowing the accommodating chamber 70 to accommodate a larger amount of working medium. This increases the heat dissipation area of ​​the working medium, thereby improving the heat dissipation effect of the electric pump. In one embodiment, the flow holes 75 include a first flow hole 731 and a second flow hole 732. The first connection section 741 includes the first flow hole 731, and the second connection section 742 includes the second flow hole 732. In a direction parallel to the axial direction of the electric pump, the first flow hole 731 is farther from the pump shaft 5 than the second flow hole 732, i.e., the minimum distance between the first flow hole 731 and the pump shaft 5 is greater than the minimum distance between the second flow hole 732 and the pump shaft 5. Alternatively, in a direction parallel to the axial direction of the electric pump, the first flow hole 731 is closer to the bottom wall 31 than the second flow hole 732. This allows the working medium to flow more easily into the accommodating chamber 70 from the first flow hole 731, which is relatively close to the bottom wall 31. This allows the working medium to flow more quickly into the accommodating chamber 70, thereby improving the heat exchange rate between the shaft stop 7 and the working medium. The working medium flows out of the accommodating chamber 70 from the second flow hole 732, which is relatively far from the bottom wall 31. This allows the accommodating chamber 70 to accommodate a larger amount of working medium, thereby increasing the heat dissipation area of ​​the working medium and thereby improving the heat dissipation effect of the electric pump.

[0085] 20 to 26 , the base 72 extends from the connection portion 74 in a direction away from the pump shaft 5 . The base 72 is fixedly connected or position-limitedly connected to the isolation sleeve 3 . In the axial direction of the electric pump, the thickness of the base 72 is greater than the thickness of the isolation sleeve 3 , so that the pump shaft limiting portion 7 has a certain structural strength.

[0086] Referring to Figures 27 to 30 , the shaft stopper 7 includes a fixing portion 71 and a base 72. The fixing portion 71 is connected to the base 72. The fixing portion 71 is fixedly connected or position-limited to the pump shaft 5, and the base 72 is fixedly connected or position-limited to the isolation sleeve 3. Referring to Figure 28 , the base 72 has a flow hole 75. Because the base 72 is relatively close to the bottom wall 31, the flow hole 75 allows the working medium to flow into the accommodating chamber 70 more quickly, which helps to improve the heat exchange rate between the shaft stopper 7 and the working medium.

[0087] 27 , the fixing portion 71 has a flow hole 75 . The fixing portion 71 is relatively far away from the bottom wall 31 . The accommodating cavity 70 can accommodate more working medium, which is beneficial to increase the heat dissipation area of ​​the working medium, thereby improving the heat dissipation effect of the electric pump.

[0088] In one embodiment, referring to Figures 29 and 30 in conjunction with Figure 28 , the flow hole 75 includes a first flow hole 731 and a second flow hole 732. The base 72 has the first flow hole 731, and the fixing portion 71 has the second flow hole 732. Along a direction parallel to the axial direction of the electric pump, the first flow hole 731 is farther from the pump shaft 5 than the second flow hole 732, i.e., the minimum distance between the first flow hole 731 and the pump shaft 5 is greater than the minimum distance between the second flow hole 732 and the pump shaft 5. Alternatively, along a direction parallel to the axial direction of the electric pump, the first flow hole 731 is closer to the bottom wall 31 than the second flow hole 732. This allows the working medium to flow more easily into the accommodating chamber 70 from the first flow hole 731, which is relatively close to the bottom wall 31. This allows the working medium to flow more quickly into the accommodating chamber 70, thereby improving the heat exchange rate between the shaft stop 7 and the working medium. The working medium flows out of the accommodating chamber 70 from the second flow hole 732, which is relatively far from the bottom wall 31. This allows the accommodating chamber 70 to accommodate a larger amount of working medium, thereby increasing the heat dissipation area of ​​the working medium and thereby improving the heat dissipation effect of the electric pump.

[0089] Referring to Figures 27 to 30, the fixing portion 71 includes a first end wall 711 and a second end wall 712. Along a direction parallel to the axial direction of the electric pump, the first end wall 711 is farther away from the bottom wall 31 of the isolation sleeve 3 than the second end wall 712. The cavity wall of the accommodating chamber 70 includes at least the second end wall 712 and the inner wall of the fixing portion 71. When the electric pump is operating, there is a working medium in the isolation cavity 30. The working medium in the isolation cavity 30 can flow into the accommodating cavity 70. The second end wall 712 and the inner wall of the fixing portion 71 can come into contact with the working medium. The second end wall 712, the inner wall of the fixing portion 71, and at least a portion of the outer wall of the shaft limiting portion 7 can come into contact with the working medium. The surface area of ​​the shaft limiting portion 7 in contact with the working medium is larger, which increases the heat dissipation area of ​​the working medium, thereby facilitating improved heat dissipation of the electric pump.

[0090] In one embodiment, please refer to Figure 26, the shaft limiting portion 7 includes a base 72, the base 72 is fixedly connected or limit-connected to the isolation sleeve 3, the base 72 has a bottom 722, the isolation sleeve 3 has a bottom wall 31, and along the direction parallel to the axial direction of the electric pump, there is a gap between at least part of the bottom 722 and the bottom wall 31, the shaft limiting portion 7 has at least one flow hole 75, the flow hole 75 is connected to the isolation chamber 30, and the flow hole 75 is connected to the accommodating chamber 70.

[0091] 20 to 23 , at least a portion of the pump shaft 5 is located in the accommodating cavity 70 , and at least a portion of the pump shaft 5 can contact the working medium in the accommodating cavity 70 , which is beneficial to increasing the heat dissipation area of ​​the working medium, thereby improving the heat dissipation effect of the electric pump.

[0092] Referring to Figures 20 to 23 , the pump shaft 5 includes a first section 51, a second section 52, and a third section 53. The second section 52 is connected to the first section 51, which is then connected to the third section 53. The second section 52 is fixedly connected or position-limited to the fixing portion 71. The first section 51 is located within the accommodating chamber 70. When the electric pump is operating, the first section 51 can contact the working medium within the accommodating chamber 70, thereby increasing the heat dissipation area of ​​the working medium and thus improving the heat dissipation effect of the electric pump. In the axial direction of the electric pump, the distance between the first section 51 and the bottom wall 31 is less than the height of the first section 51. Since the second section 52 is connected to the first section 51, the second section 52 can be farther from the bottom wall 31, resulting in a higher axial height of the accommodating chamber 70, which can provide a larger volume for the accommodating chamber 70. Please refer to Figures 9 to 11. The pump shaft 5 has a second division 52 and a third division 53. The second division 52 is connected to the third division 53. The second division 52 is fixedly connected or limit-connected to the fixing portion 71. The cavity wall of the accommodating cavity 70 includes the bottom wall of the pump shaft 5. When the electric pump is working, the bottom wall of the pump shaft 5 can contact the working medium in the accommodating cavity 70, which is beneficial to increase the heat dissipation area of ​​the working medium, thereby improving the heat dissipation effect of the electric pump.

[0093] The second division 52 is fixedly connected or limitedly connected to the fixing portion 71, and the pump shaft 5 and the shaft limiting portion 7 cannot rotate relative to each other. Specifically, the second division 52 and the fixing portion 71 are interference fit to prevent the pump shaft 5 and the shaft limiting portion 7 from rotating. In other embodiments, the pump shaft 5 and the shaft limiting portion 7 may be fixedly connected by other means such as welding to prevent rotation therebetween.

[0094] Referring to Figures 20 to 25 , in the radial direction of the electric pump, the width of the fixing portion 71 is smaller than the width of the base 72. The radial width of the base 72 is relatively large, which allows the base 72 to have a larger contact area with the isolation sleeve 3, thereby improving the fixing effect of the shaft stopper 7. In other embodiments, referring to Figures 12 to 15 , in the radial direction of the electric pump, the width of the fixing portion 71 is equal to the width of the base 72, and the production process of the shaft stopper 7 is simple.

[0095] In one embodiment, referring to Figures 27 and 29 , the fixing portion 71 includes a groove 714, with the pump shaft 5 fixedly or positionally connected to the groove 714. The groove 714 is recessed from the first end wall 711 toward the bottom wall 31. The groove 714 is not connected to the accommodating chamber 70, and the pump shaft 5 does not come into contact with the working medium in the accommodating chamber 70. This prevents the pump shaft 5 from being corroded by the working medium, facilitating the normal operation of the electric pump.

[0096] In one embodiment, referring to Figures 20 to 25, the fixing portion 71 has a first end wall 711, and the fixing portion 71 has a mounting hole 715. The mounting hole 715 extends from the first end wall 711 toward the bottom wall 31, and the mounting hole 715 is connected to the accommodating cavity 70. The second section 52 of the pump shaft 5 is located in the mounting hole 715. The bottom wall of the pump shaft 5 can contact the working medium in the accommodating cavity 70, which is beneficial to increase the heat dissipation area of ​​the working medium, thereby improving the heat dissipation effect of the electric pump.

[0097] In one embodiment, referring to Figures 28 and 30, the fixing portion 71 has a mounting hole 715, which passes through the first end wall 711 and the second end wall 712. The mounting hole 715 is connected to the accommodating cavity 70, and the second section 52 of the pump shaft 5 is located in the mounting hole 715. The bottom wall of the pump shaft 5 can be in contact with the working medium in the accommodating cavity 70, which is beneficial to increase the heat dissipation area of ​​the working medium, thereby improving the heat dissipation effect of the electric pump.

[0098] Please refer to Figures 20 to 26. The second division 52 is located in the mounting hole 715. In the radial direction of the electric pump, the width of the mounting hole 715 is W. In the axial direction of the electric pump, the height at which the pump shaft 5 contacts the shaft limit portion 7 is H (or the height of the second division is H). The ratio of W to H ranges from 1:1 to 3, which is beneficial to improving the concentricity of the shaft limit portion 7 and the pump shaft 5. When the electric pump is working, the pump shaft 5 is not easy to swing, the vibration amplitude of the pump shaft 5 is small, and the noise is small, which is beneficial to improving the service life of the electric pump.

[0099] Please refer to Figures 20 and 24. The bottom wall 31 of the isolation sleeve 3 includes a first sub-bottom wall 311 and a second sub-bottom wall 312. The second sub-bottom wall 312 is located on the periphery of the first sub-bottom wall 311, for example, the second sub-bottom wall 312 is located on the outer periphery of the first sub-bottom wall 311; the base 72 is fixedly connected or limit-connected to the second sub-bottom wall 312, and the base 72 contacts the second sub-bottom wall 312. The cavity wall of the accommodating cavity 70 includes the first sub-bottom wall 311. When the electric pump is working, there is working medium in the isolation cavity 30, and the first sub-bottom wall 311 can contact the working medium. The area in which the isolation sleeve 3 contacts the working medium is relatively large, which is beneficial to increase the heat dissipation area of ​​the working medium, thereby improving the heat dissipation effect of the electric pump.

[0100] The limiting connection mentioned in this application includes a clearance fit setting, an interference fit setting, and a transition fit setting; the fixed connection includes other connection methods such as welding and bonding.

[0101] 31 and 32 , the present application provides an electric pump 100 including a pump housing 1, a rotating assembly 12, an isolation sleeve 3, and a pump shaft 5; the stator assembly 2 includes a stator winding, and the stator assembly 2 is fixedly connected to the motor pump housing 112. Specifically, the motor pump housing 112 can be formed by injection molding with at least the stator assembly 2 as an insert. Of course, the outer wall of the stator assembly 2 can also be interference fit with the motor pump housing 112. The isolation sleeve 3 is limitedly fitted with the inner wall of the stator assembly 2. It should be noted that the limited fit here includes but is not limited to interference fit, transition fit, or clearance fit. The electric pump can also include a control board assembly 6, which is electrically connected to the stator assembly 2 via a pin 21. Of course, the electric pump may not include the control board assembly 6. In this embodiment, the electric pump 100 includes a control board assembly 6, which is electrically connected to the stator assembly 2 via a pin 21. The pump housing 111 is fixedly connected to the motor pump housing 112, and the bottom cover 113 is fixedly connected to the motor pump housing 112; specifically, the bottom cover 113 and the motor pump housing 112 are welded and fixed, and the pump housing 111 and the motor pump housing 112 are fixedly connected by screws. The electric pump 100 has a pump inner cavity 22, and the rotating assembly 12 is located in the pump inner cavity 22. The pump inner cavity 22 includes a rotor cavity 101 and an impeller cavity 102, and the rotor cavity 101 and the impeller cavity 102 are connected. The electric pump has a first cavity 10 and a second cavity 222, and the first cavity 10 and the second cavity 222 are not connected. The stator assembly 2 is located in the first cavity 10, and the rotating assembly 12 is located in the second cavity 222. The first cavity 10 is located on one side of the isolation sleeve 3, and part of the second cavity 222 is located on the other side of the isolation sleeve 3. The rotating assembly 12 includes a rotor assembly 121 and an impeller assembly 122. The rotor assembly 121 includes a rotor portion 1211 and an injection molding portion 1212. The rotor portion 1211 includes a permanent magnet, and the permanent magnet is located in the injection molding portion 1212. At least part of the rotor assembly 121 is located in the rotor cavity 101, and the impeller assembly 122 is located in the impeller cavity 102. The working medium can flow through the pump cavity 22. The electric pump 100 may also not include the pump housing 111. The pump housing 111 is integrated into the external structure. Such a setting is more conducive to the integrated design of the electric pump 100, making the structure of the electric pump 100 more compact, and more conducive to the miniaturization and lightweight of the structure of the electric pump 100. The pump housing 111 has an inlet 1111 and an outlet 1112. The inlet 1111 is used for the working medium to flow into the electric pump, and the outlet 1112 is used for the working medium to flow out of the electric pump. When the electric pump 100 is working, the electric pump 100 is connected to an external power supply, and the excitation magnetic field generated by the stator winding is controlled by controlling the current of the stator winding. The rotating component 12 rotates around the pump shaft 5 under the action of the excitation magnetic field, so that the working medium entering the pump cavity 22 through the inlet 1111 rotates with the rotating component 12, and the working medium will leave the pump cavity 22 through the outlet 1112 under the action of centrifugal force.

[0102] Referring to Figures 31 to 33 , in this embodiment, the electric pump 100 includes a control board assembly 6, which includes a substrate 141 and electronic components 142. The electronic components 142 include heat-generating electronic components, including but not limited to common heat-prone electronic components such as diodes, MOSFETs, inductors, resistors, and capacitors. The isolation sleeve 3 is made of metal. Specifically, the wall portion corresponding to the rotor cavity 101 includes a bottom 201, which is made of metal. At least a portion of the control board assembly 6 is in direct or indirect contact with the bottom 201. Specifically, for indirect contact between at least a portion of the control board assembly 6 and the bottom 201, the electric pump 100 includes thermal grease or thermally conductive silicone 23, which is filled between at least a portion of the control board assembly 6 and the bottom 201. The working medium within the first cavity 10 can dissipate heat from the control board assembly 6 and / or the stator assembly 2. Of course, the electric pump 100 may also not include the control board assembly 6. If the control board assembly 6 is not included, the working medium in the first chamber 10 can dissipate heat from the stator assembly 2. To quickly dissipate heat from the control board assembly 6 and / or the stator assembly 2, a return channel 18 is typically provided. Through the return channel 18, the working medium in the rotor chamber 101 can enter the impeller chamber 102 and then exit the rotor chamber 101 under the centrifugal force generated by the rotation of the impeller assembly 122. Of course, in other embodiments, the working medium can also enter the rotor chamber 101 through the return channel 18.

[0103] As an implementation, please refer to Figures 31 to 34, 38, and 39, which show an electric pump 100. The rotating assembly 12 includes a rotor assembly 121. The rotor assembly 121 has a limiting hole 124. Part of the pump shaft 5 is located in the limiting hole 124. The electric pump 100 has a rotor cavity 101. The rotor cavity 101 can circulate a working medium. At least part of the rotor assembly 121 is located in the rotor cavity 101. The electric pump 100 has a return channel 18. The return channel 18 includes a flow channel 181 and an internal flow channel 182. The overflow channel 181 is connected to the internal flow channel 182, and the rotor assembly 121 has at least a portion of the overflow channel 181. Along the radial direction of the electric pump 100, there is a gap between the wall 1813 corresponding to the overflow channel 181 and the wall 1241 corresponding to the limiting hole 124, and part of the rotor assembly 121 is located in the gap. It can also be understood that the overflow channel 181 is not directly connected to the limiting hole 124, and part of the pump shaft 5 is located in the internal flow channel 182. The wall corresponding to the internal flow channel 182 includes part of the outer wall of the pump shaft 5. In this manner, the electric pump 100 has a return channel 18, which includes an overflow channel 181 and an internal flow channel 182. The overflow channel 181 communicates with the internal flow channel 182. The rotor assembly 121 has at least a portion of the overflow channel 181, which is not directly connected to the limiting hole 124. This allows the limiting hole 124, which cooperates with the pump shaft 5, to form a complete circle in the circumferential direction. When the rotating assembly 12 rotates around the pump shaft 5, the wall portion corresponding to the limiting hole 124 is in a position that is limited and cooperates with the pump shaft 5 in the circumferential direction. This helps reduce the swing of the rotating assembly 12 and, in turn, helps reduce the noise of the electric pump 100. Furthermore, the rotating assembly 12 includes a shaft sleeve 123, which is fixedly connected or limitedly connected to the rotor assembly 121 and has a limiting hole 124. In this manner, first, at least a portion of the wall corresponding to the circulation channel is disposed within the rotor assembly. This application does not remove material from the sleeve 123. It is understood that at least a portion of the circulation channel is not disposed within the sleeve 123, which helps improve the structural strength of the sleeve 123. Third, the wall corresponding to the internal flow channel 182 includes a portion of the outer wall 155 of the pump shaft 5. Because the working medium flows through the internal flow channel 182, when the rotating assembly 12 rotates, for example, especially at high speeds, the friction between the rotating assembly 12 and the pump shaft 5 generates heat. This heat generated by the rotating assembly 12 and / or the pump shaft 5 can be transferred to the working medium within the internal flow channel 182, thereby dissipating heat from the rotating assembly 12 and / or the pump shaft 5 and thereby improving the lifespan of the rotating assembly 12 and / or the pump shaft 5. Fourth, the absence of the return channel 18 on the sleeve 123 helps reduce the difficulty of manufacturing the sleeve 123, laying a foundation for reducing the production cost of the electric pump. Please refer to FIG. 34 , which shows a return flow path S1 for the working medium in the rotor chamber 101 to enter the impeller chamber 102 .

[0104] As an implementation method, please refer to Figures 31 to 33. The sleeve 123 includes a first sleeve 1231 and a second sleeve 1232. The rotor assembly 121 includes a rotor portion 1211 and an injection molding portion 1212. The injection molding portion 1212 is formed by injection molding at least the rotor portion 1211, the first sleeve 1231, and the second sleeve 1232. The first sleeve 1231 is located on one side of the inner flow channel 182, and the second sleeve 1232 is located on the other side of the inner flow channel 182. The pump 100 includes a rotor chamber 101, in which at least a portion of a rotor assembly 121 is located. The rotor chamber 101 is capable of circulating a working medium. The wall portion corresponding to the rotor chamber 101 includes a bottom portion 201. The first sleeve 1231 is located closer to the bottom portion 201 relative to the second sleeve 1232. The wall portion corresponding to the internal flow channel 182 includes an upper wall portion 1231a of the first sleeve 1231, a lower wall portion 1232a of the second sleeve 1232, and a portion of the injection molded portion 1212. In this manner, first, while reducing the sleeve material, the mating area between the sleeve and the shaft is reduced. This helps reduce the friction area of ​​the rotor assembly 121 while ensuring mating between the shaft and the rotor assembly, thereby improving the life of the rotor assembly 121 and / or the pump shaft 5.

[0105] Further, please refer to Figures 31 to 34. The first sleeve 1231 and the second sleeve 1232 can be arranged adjacent to each other, and of course they can also be arranged in other ways. As an implementation method, the flow channel 181 includes a first flow channel 1811 and a second flow channel 1812. The first flow channel 1811 is located on one side of the inner flow channel 182, and the second flow channel 1812 is located on the other side of the inner flow channel 182. The first flow channel 1811 is connected to the second flow channel 1812 through the inner flow channel 182. In this way, first, since the inner flow channel 182 is arranged between the first sleeve 1231 and the second sleeve 1232, it can be understood that the first flow channel 1811 and the second flow channel 1812 are connected with the help of the inner flow channel 182, which is conducive to reducing the length of the first flow channel 1811 in the axial direction of the electric pump. At the same time, it is conducive to reducing the length of the second flow channel 1812 in the axial direction of the electric pump, and is more conducive to realizing the processing and manufacturing of the first flow channel 1811 and / or the second flow channel 1812, reducing the difficulty of manufacturing the first flow channel 1811 and / or the second flow channel 1812.

[0106] As an implementation method, please refer to Figures 31 and 35. The first flow channel 1811 is located radially outside the first sleeve 1231. The wall portion corresponding to the first flow channel 1811 includes the outer wall portion of the first sleeve 1231 and the injection molding portion 1212, or the wall portion corresponding to the first flow channel 1811 includes the injection molding portion 1212. The second flow channel 1812 includes an axial hole 151 and a transverse hole 152. The pump shaft 5 includes an upper end 153 and a lower end 154. Along the axial direction of the pump shaft 5, the axial hole 151 extends from the upper end 153 to the lower end 154. One end of the transverse hole 152 is connected to the axial hole 151, and the other end of the transverse hole 152 is connected to the inner flow channel 182. In this way, the flow channel 181 is partially disposed on the injection molding portion 1212 and partially disposed on the pump shaft 5, which helps to reduce the difficulty of injection molding of the rotating assembly 12.

[0107] Please refer to FIG35 , where the bypass channel 1114 can pass through the support portion 1113 and communicate with the inlet 1111. Of course, the bypass channel 1114 can also be provided on the impeller assembly 122. Further, as an implementation method, the electric pump 100 includes a pump housing 11, the pump housing 11 having a support portion 1113, the support portion 1113 being positionally engaged with the pump shaft 5, the pump housing 11 having an inlet 1111, the support portion 1113 having a bypass channel 1114, one end of the bypass channel 1114 being communicated with the shaft hole 151, and the other end of the bypass channel 1114 being communicated with the inlet 1111. In this way, the bypass channel 1114 is provided on the support portion 1113 of the pump housing 11, thereby reducing the impact of the bypass channel 1114 on the impeller assembly 122.

[0108] As an implementation, referring to Figures 31 to 34 , a first flow channel 1811 is located radially outward of the first sleeve 1231. The wall portion corresponding to the first flow channel 1811 includes the outer wall portion of the first sleeve 1231 and the injection molded portion 1212, or the wall portion corresponding to the first flow channel 1811 includes the injection molded portion 1212. A second flow channel 1812 is located radially outward of the second sleeve 1232. The wall portion corresponding to the second flow channel 1812 includes the outer wall portion 155 of the second sleeve 1232, or the wall portion corresponding to the second flow channel 1812 includes the injection molded portion 1212. One end of the second flow channel 1812 is connected to the inner flow channel 182. In this manner, compared to not providing a partial flow channel 181 on the pump shaft 5, while achieving circulation of the working medium within the rotor cavity 101, it is beneficial to improve the structural strength of the pump shaft 5, further laying a certain foundation for increasing the life of the electric pump.

[0109] As an implementation, referring to Figures 31 to 34 , an electric pump 100 includes a pump housing 11 having an inlet 1111, a rotating assembly 12 including an impeller assembly 122, and an inlet channel 110. One end of the inlet channel 110 communicates with the second flow channel 1812, and the other end of the inlet channel 110 communicates with the inlet 1111. In this manner, there is no need to provide a bypass channel 1114 on the support portion 1113 of the pump housing 11. The unique structure of the impeller assembly 122 directly connects the second flow channel 1812 to the inlet 1111, thereby simplifying the structure of the electric pump 100.

[0110] As an implementation method, please refer to Figures 31 and 36. The electric pump 100 includes a shaft stopper 7, which has an accommodating cavity 70. The wall portion corresponding to the rotor cavity 101 includes a bottom 201. The pump shaft 5 is fixed to the bottom 201 via the shaft stopper 7. The pump shaft 5 includes a vertical hole 156 and a transverse groove 157. The pump shaft 5 includes an upper end 153 and a lower end 154. Along the axial direction of the pump shaft 5, the vertical hole 156 extends from the lower end 154 toward the upper end 153. One end of the vertical hole 156 is connected to the accommodating cavity 70, and the other end of the vertical hole 156 is connected to the internal flow channel 182 through the transverse groove 157. The accommodating cavity 70 is connected to the rotor cavity 101. In this way, while achieving a fixed connection between the pump shaft 5 and the isolation sleeve 3, it is also beneficial to increase the contact area between the working medium and the bottom, thereby facilitating heat dissipation of the control board assembly 6.

[0111] Please refer to Figures 31 and 36 again. In order to quickly circulate the working medium in the accommodating chamber 70 and thereby increase the circulation speed of the working medium at the bottom of the rotor chamber 101, the shaft limiting portion 7 further has a circulation hole 75. The circulation hole 75 penetrates the wall corresponding to the accommodating chamber 70 along the thickness direction of the wall corresponding to the accommodating chamber 70. One end of the circulation hole 75 is connected to the accommodating chamber 70, and the other end of the circulation hole 75 is connected to the rotor chamber 101. In this way, the working medium in the accommodating chamber 70 can be effectively led out to the rotor chamber 101, thereby facilitating the rapid circulation speed of the working medium at the bottom of the rotor chamber 101 and facilitating the heat dissipation of the control board assembly 6.

[0112] As another implementation method, please refer to Figures 31 and 37, the injection molding part 1212 includes a first part 1212a and a second part 1212b, at least part of the rotor part 1211 is located in the first part 1212a, at least part of the first sleeve 1231 is located in the second part 1212b, the radial direction dimension of the first part 1212a is smaller than the radial direction dimension of the second part 1212b, the inner flow channel 182 extends along the axial direction of the electric pump 100 toward the direction of the first part 1212a, the wall portion corresponding to the inner flow channel 182 includes the first part 1212a, and the electric pump 100 has a water groove 19, one end of the water groove 19 is connected to the rotor cavity 101, and the other end of the water groove 19 is connected to the inner flow channel 182. Specifically, the water channel 19 is disposed between the first sleeve 1231 and the second sleeve 1232, which helps increase the capacity of the internal flow channel 182 to store the working medium, thereby facilitating heat dissipation of the rotor assembly 121. This also increases the axial length of the first sleeve 1231 and the second sleeve 1232, thereby reducing the swing of the rotating assembly 12 when the electric pump 100 is operating. It should be noted that the aforementioned "radial direction" is perpendicular to the axial direction of the electric pump 100, which is the direction in which the centerline of the shaft of the electric pump 100 extends.

[0113] It should be noted that the above embodiments are only used to illustrate the present application and are not intended to limit the technical solutions described in the present application. Although this specification has described the present application in detail with reference to the above embodiments, ordinary technicians in this field should understand that technicians in the relevant technical field can still modify or replace the present application with equivalents, and all technical solutions and improvements that do not depart from the spirit and scope of the present application should be included in the scope of the claims of the present application.

Claims

1. An electric pump, characterized in that: The electric pump comprises a rotor assembly (4), a pump shaft (5), a shaft stopper (7) and a spacer sleeve (3); the rotor assembly (4) is located on the outer periphery of the pump shaft (5); the pump shaft (5) is fixedly connected or limit-connected to the shaft stopper (7); the shaft stopper (7) comprises a first welding portion (81); the spacer sleeve (3) comprises a bottom portion (32); the bottom portion (32) comprises a second welding portion (82); the first welding portion (81) and the second welding portion (82) are fixedly welded; The bottom (32) has a first end face (321) and a second end face (322); along a direction parallel to the axial direction of the electric pump, the first end face (321) is closer to the shaft limiting portion (7) relative to the second end face (322); the area of ​​the projection of the second welding portion (82) on the first end face (321) is smaller than the area of ​​the projection of the shaft limiting portion (7) on the first end face (321); and there is a spacing between the second welding portion (82) and the second end face (322).

2. The electric pump according to claim 1, characterized in that: The shaft limiting portion (7) has a third end face (721), the extension direction of the first end face (321) is parallel to the extension direction of the third end face (721), the first welding portion (81) extends from the third end face (721) in a direction away from the shaft limiting portion (7), and along a direction parallel to the axial direction of the electric pump, the area of ​​the projection of the first welding portion (81) on the third end face (721) is smaller than the area of ​​the third end face (721).

3. The electric pump according to claim 2, characterized in that: Along a direction parallel to the axial direction of the electric pump, the first welding portion (81) has a first distance, the distance from the first end surface (321) to the second end surface (322) is a second distance, and the ratio of the first distance to the second distance is 0.6-2.

4. The electric pump according to claim 2, characterized in that: The first welding portion (81) comprises a plurality of first welding protrusions (811), and the projection of the first welding protrusions (811) on the third end surface (721) is circular or polygonal; or a line connecting the projections of the first welding protrusions (811) on the third end surface (721) is a circle or a polygon; Alternatively, the projection of the first welding portion (81) on the third end surface (721) is circular or polygonal.

5. The electric pump according to claim 3, characterized in that: The first welding portion (81) includes a plurality of first welding protrusions (811), and the projection of the first welding protrusions (811) on the third end surface (721) is circular or polygonal; or a line connecting the projections of the first welding protrusions (811) on the third end surface (721) is a circle or a polygon; Alternatively, the projection of the first welding portion (81) on the third end surface (721) is circular or polygonal.

6. The electric pump according to claim 1, characterized in that: The second welding portion (82) extends from the first end surface (321) in a direction away from the second end surface (322), and along a direction parallel to the axial direction of the electric pump, the projection area of ​​the second welding portion (82) on the first end surface (321) is smaller than the area of ​​the first end surface (321).

7. The electric pump according to claim 6, characterized in that The shaft limiting portion (7) comprises a base (72), the base (72) having a third end face (721), the extension direction of the third end face (721) being parallel to the extension direction of the first end face (321), and the thickness of the second welding portion (82) is smaller than the thickness of the base (72) along a direction parallel to the axial direction of the electric pump.

8. The electric pump according to claim 5, characterized in that The second welding portion (82) comprises a plurality of second welding protrusions (821), and the projection of the second welding protrusions (821) on the first end surface (321) is circular or polygonal; Or the second welding protrusion (821) is a circle or a polygon after connecting the projections of the first end surface (321); Alternatively, the projection of the second welding portion (82) on the first end surface (321) is circular or polygonal.

9. The electric pump according to claim 6, characterized in that: The second welding portion (82) comprises a plurality of second welding protrusions (821), and the projection of the second welding protrusions (821) on the first end surface (321) is circular or polygonal; Or the second welding protrusion (821) is a circle or a polygon after connecting the projections of the first end surface (321); Alternatively, the projection of the second welding portion (82) on the first end surface (321) is circular or polygonal.

10. The electric pump according to claim 1, characterized in that The shaft limiting portion (7) covers a portion of the first end surface (321), and the shaft limiting portion (7) comprises a base (72). The base (72) is fixedly connected to the bottom (32), and the thickness of the bottom (32) is smaller than the thickness of the base (72).

11. The electric pump according to claim 2, characterized in that: The shaft limiting portion (7) covers a portion of the first end surface (321), and the shaft limiting portion (7) comprises a base (72). The base (72) is fixedly connected to the bottom (32), and the thickness of the bottom (32) is smaller than the thickness of the base (72).

12. A method for assembling an electric pump, characterized in that: The assembly method of the electric pump comprises: Obtaining the shaft limiting portion (7) and the isolation sleeve (3); The shaft limiting portion (7) and the isolation sleeve (3) are fixedly connected: a first welding portion (81) of the shaft limiting portion (7) and a second welding portion (82) of the isolation sleeve (3) are fixedly welded, and during welding, a portion of the bottom portion (32) of the isolation sleeve (3) is melted in a direction parallel to the axial direction of the electric pump.

13. The assembly method according to claim 12, characterized in that: A pump shaft (5) is obtained, and the pump shaft (5) and the shaft limiting portion (7) are fixedly connected or limit-connected; when the shaft limiting portion (7) and the isolation sleeve (3) are fixedly connected, a first welding electrode and a second welding electrode are provided, so that the first welding electrode contacts the isolation sleeve (3) and the second welding electrode contacts the pump shaft (5).

14. The electric pump according to any one of claims 1 to 11, characterized in that: The electric pump comprises an isolation sleeve (3), a rotor assembly (4), a pump shaft (5) and a shaft limiting portion (7); the rotor assembly (4) is located on the outer periphery of the pump shaft (5); the isolation sleeve (3) is fixedly connected or limit-connected to the shaft limiting portion (7); the isolation sleeve (3) has an isolation cavity (30); the rotor assembly (4) and at least part of the pump shaft (5) are located in the isolation cavity (30); the shaft limiting portion (7) has a accommodating cavity (70); and the accommodating cavity (70) is communicated with the isolation cavity (30).

15. The electric pump (100) according to any one of claims 1 to 11, characterized in that: The electric pump (100) comprises a rotating assembly (12) and a pump shaft (15); the rotating assembly (12) comprises a rotor assembly (121); the rotor assembly (121) has a limiting hole (124); a portion of the pump shaft (15) is located in the limiting hole (124); the electric pump (100) has a rotor cavity (101); the rotor cavity (101) is capable of circulating a working medium; at least a portion of the rotor assembly (121) is located in the rotor cavity (101); the electric pump (100) has a return channel (18); the return channel (18) comprises a flow channel (181); along the radial direction of the electric pump (100), the flow channel (181) is located radially outside the limiting hole (124); the rotating assembly (12) comprises a shaft sleeve (123); the flow channel (181) is located radially outside the shaft sleeve (123).

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