Axial pressure-boosted water pump impeller and processing method thereof

Abstract

The application relates to a shaft-flow pressurized water pump impeller and a processing method thereof. The water pump impeller comprises a bottom shell and a top cover arranged coaxially, the bottom shell comprises a shell main body and at least three lower blades, the top cover comprises a cover main body and at least three upper blades, the shell main body comprises a central hole and an outer convex curved surface, the lower blades extend spirally along the outer convex curved surface from the edge to the central hole, the cover main body comprises a shaft-flow hole and an inner concave curved surface, the lower blades and the upper blades are arranged alternately and a curved flow channel is formed between the lower blades and the upper blades. The outer convex curved surface and the inner concave curved surface are formed with recessed inserting grooves corresponding to the positions of the convex inserting ribs, the groove bottoms of the inserting grooves are partially protruded to form expansion convex ribs, the expansion convex ribs and the expansion curved surfaces are complementary; the water pump impeller is integrally connected by ultrasonic welding. The convex inserting ribs and the inserting grooves are matched and positioned, the expansion convex ribs and the expansion curved surfaces are complementarily connected during ultrasonic welding, not only the bonding area is enlarged, but also the curved surface connecting textures are formed, and the tensile strength is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of water pump impeller technology, and in particular to an axial flow booster water pump impeller and its processing method. Background Technology

[0002] The water pump impeller, driven by power, outputs liquid at a preset pressure and maintains a stable liquid flow rate. The impeller can be made of plastic and welded using ultrasonic welding. For example, publication number CN218542693U provides an impeller structure and a water pump and cleaning machine using this impeller structure. And publication number CN114033743A provides an automotive electronic water pump impeller rotor.

[0003] The existing production process is as follows: the impeller is processed using injection molds and is divided into a main body with blades and a cover body. The cover body can be provided with grooves, and the blade ends are provided with flat ribs. After the ribs are inserted into the grooves and fitted, they are formed by ultrasonic welding.

[0004] The existing structure is only suitable for welding planar impellers. When dealing with impellers with large blade curvature distributed on curved surfaces, several key problems arise: 1. Difficulty in structural implementation: It's impossible to concentrate the blades in the main body, making it difficult to match the design requirements of the curved surface. 2. Poor production quality: The cover section uses a single welding method, resulting in large deformation of the cover itself and lower weld strength than the forming strength of the blades in the main body, easily producing defective products and increasing the production scrap rate. 3. The small contact area between the planar ribs and grooves affects the tensile strength of the blades, thus requiring improvement. Summary of the Invention

[0005] To overcome the problems existing in related technologies, this invention provides an axial flow booster water pump impeller and its processing method, in order to solve the technical problems of difficult impeller production, large concentrated deformation at the welding parts, and low tensile strength of the blade welding parts.

[0006] According to a first aspect of the present invention, an axial flow boosting water pump impeller is provided. The water pump impeller includes a bottom shell and a top cover arranged coaxially. The bottom shell includes a shell body and at least three uniformly distributed lower blades. The top cover includes a cover body and at least three upper blades. The shell body includes a central hole and an outwardly convex surface that gradually curves and protrudes from the edge toward the central hole. The lower blade extends spirally from the edge toward the central hole along the outwardly convex surface. The cover body includes an axial flow hole and an inwardly concave surface that matches the outwardly convex surface. The upper blade extends spirally from the edge toward the axial flow hole along the inwardly concave surface. The lower blade and the upper blade are alternately arranged and a curved flow channel is formed between them. Both the lower blade and the upper blade have raised inserts at their ends. At least a portion of the raised inserts have recessed expansion surfaces at their ends. The outer and inner convex surfaces have recessed insertion grooves at the positions corresponding to the raised inserts. The bottom of the insertion grooves has raised ribs at their ends. The expansion ribs and the expansion surfaces are complementary. The water pump impeller is welded together as a single unit using ultrasonic welding.

[0007] In one embodiment, the protruding insert includes a lower insert forming a partial protrusion from the end of the lower blade, a first insert forming a second insert forming a partial, spaced protrusion from the end of the upper blade, and the insertion groove includes a third slot located in the cover body, and a first slot and a second slot located in the shell body. The expansion rib includes a first rib located in the second slot and a second rib located in the third slot. The expansion surface includes a first surface located on the lower insert and a second surface located on the second insert, wherein the surface area of ​​the first surface is greater than the cross-sectional area of ​​the lower insert, and the surface area of ​​the second surface is greater than the cross-sectional area of ​​the second insert. The first slot is adapted to the first insert bar, the second slot is adapted to the second insert bar, and the lower insert bar is adapted to the third slot.

[0008] In one embodiment, the rotation area of ​​the first insert bar and the rotation area of ​​the lower insert bar partially overlap or intersect, and the rotation area of ​​the second insert bar and the rotation area of ​​the lower insert bar partially overlap or intersect.

[0009] In one embodiment, the upper blade and the lower blade have the same curved surface shape. The upper blade includes a continuous flow-guiding section, an extension section and a lifting section. The cross-section of the flow-guiding section is arc-shaped and protrudes towards the axial flow hole. The lifting section intersects at the edge and its end is parallel to the center line of the axial flow hole. The extension section extends obliquely along the concave curved surface.

[0010] In one embodiment, the thickness of the protruding rib is less than the thickness of the upper blade.

[0011] In one embodiment, the curved flow channel has an axial height difference between its inlet at one end of the axial flow hole and its outlet at the edge of the pump impeller, and its cross-sectional area gradually increases from the axial flow hole toward the edge.

[0012] In one embodiment, the expansion surface is an arc-shaped groove, a triangular groove, or a trapezoidal groove.

[0013] In one embodiment, the protrusion direction of the protruding rib is parallel to the center line of the axial flow hole, and adjacent upper and lower blades at least partially overlap on the projection plane, wherein the projection plane is a plane perpendicular to the axis.

[0014] According to a second aspect of the present invention, a method for processing a water pump impeller is provided, wherein the water pump impeller as described above is processed, the processing method comprising: Align and assemble the bottom shell and top cover to form an assembly; Place the water pump impeller in the ultrasonic device; The ultrasonic device is controlled to press for 1-2 seconds under a pre-pressure of 0.3MPa-0.35MPa to make the upper blade and the outward convex curved surface fit together, and the lower blade and the inward concave curved surface fit together. The ultrasonic equipment is controlled to output corresponding welding pressure and welding amplitude so that ultrasonic welding is completed at the joint of the assembled parts to form a water pump impeller. Remove the water pump impeller.

[0015] In one embodiment, the ultrasonic device is controlled to output corresponding welding pressure and welding amplitude, and then: Reduce the pressure of the ultrasonic device to a holding pressure of 0.3 MPa-0.35 MPa; The water pump impeller is subjected to a pressure delay of 0.8 s - 1.2 s to allow the weld to cool naturally to below the glass transition temperature of the substrate.

[0016] The technical solutions provided by the embodiments of the present invention can include the following beneficial effects: both the bottom shell and the top cover are provided with blade structures, with lower and upper blades alternately distributed, thereby dispersing the welding parts, reducing overall deformation, and ensuring balanced pressure in all directions, which can improve the tightness of the welded parts and thus improve the welding effect. The protruding ribs and the insertion grooves are positioned in conjunction, and the expanded ribs and expanded curved surfaces complement each other during ultrasonic welding, not only increasing the bonding area but also forming a curved surface connection texture, greatly improving tensile strength. Furthermore, the alternating distribution of lower and upper blades ensures that the welding parts are alternately distributed, with the blades on both sides of each welding part being integrally formed blade roots, thereby improving the overall tensile strength of the impeller. The blades extend in a spiral pattern, and the spatial layout adjustment increases the output velocity and lift of the pump impeller. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0018] Figure 1 This is a schematic diagram of the structure of a water pump impeller according to one embodiment.

[0019] Figure 2 This is a schematic diagram illustrating the assembly of the bottom shell and the top cover according to one embodiment.

[0020] Figure 3This is an assembly schematic diagram showing the complementary relationship between the protruding insert and the expansion rib in the insertion groove and the expansion curved surface, according to one embodiment.

[0021] Figure 4 This is a schematic diagram illustrating an ultrasonic device according to one embodiment.

[0022] Figure 5 This is a flowchart illustrating a processing method according to one embodiment.

[0023] Figure 6 This is a schematic diagram of the top cover structure according to one embodiment.

[0024] Figure 7 This is a schematic diagram of the bottom shell structure according to one embodiment.

[0025] Figure 8 This is a schematic diagram of the bottom of the bottom shell according to one embodiment.

[0026] In the figure, the bottom shell is 10; the cover body is 11; the upper blade is 12; the flow section is 121; the extension section is 122; the lifting section is 123; the axial flow hole is 13; the concave curved surface is 14; the protruding insert is 15; the first insert is 151; the second insert is 152; the lower insert is 153; the top cover is 20; the shell body is 21; the lower blade is 22; the center hole is 23; the outward convex curved surface is 24; the insertion groove is 25; the first slot is 251; the second slot is 252; the third slot is 253; the expansion rib is 26; the first rib is 261; the second rib is 262; the expansion curved surface is 27; the first curved surface is 271; the second curved surface is 272; the center insert is 30; the ultrasonic equipment is 40; the tooling table is 50; the arc-shaped positioning groove is 51; and the center protruding column is 52. Detailed Implementation

[0027] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0028] like Figures 1 to 4As shown, this invention provides an axial flow booster pump impeller. The pump impeller includes a bottom shell 10 and a top cover 20 coaxially arranged. The bottom shell 10 includes a central hole 23, and a central insert 30 is fixedly installed at the central hole 23. The central insert 30 is used to connect a motor or other power shaft to drive the pump impeller to rotate. The top cover 20 is provided with an axially penetrating axial flow hole 13, which guides liquid into the pump impeller and outputs it after acceleration and pressurization by the pump impeller. The diameter of the axial flow hole 13 is larger than the diameter of the central hole 23 to guide liquid into the pump impeller.

[0029] The bottom shell 10 includes a shell body 21 and at least three evenly distributed lower blades 22. The shell body 21 and the lower blades 22 are integrally formed. Preferably, the number of lower blades 22 can be three, four, or five. The top cover 20 includes a cover body 11 and at least three evenly distributed upper blades 12. The upper blades 12 and the cover body 11 are integrally formed. The upper blades 12 and the lower blades 22 correspond to each other, and the lower blades 22 and the upper blades 12 are alternately arranged, forming a curved flow channel between them.

[0030] The pump impeller is welded together using ultrasonic welding. The end of the upper blade 12 is welded to the housing body 21 as a whole, and the end of the lower blade 22 is welded to the cover body 11 as a whole. More preferably, the welding curve of the upper blade 12 and the intersection line of the lower blade 22 and the housing body 21 have the same shape. Based on the same principle, the welding curve of the lower blade 22 and the intersection line of the upper blade 12 and the cover body 11 have the same shape.

[0031] The shell body 21 includes a central hole 23 and an outwardly convex surface 24 that gradually curves and protrudes from the edge toward the central hole 23. The lower blade 22 extends spirally along the outwardly convex surface 24 from the edge toward the central hole 23. The central hole 23 passes through the shell body 21 in the center. The shell body 21 protrudes from the edge toward the center, forming a trumpet-shaped curved surface structure.

[0032] The lower blade 22 has a curved thin-walled structure and a spiral structure along the convex curved surface 24. The edge of the convex curved surface 24 extends spirally toward the central hole 23. For example, the lower blade 22 extends spirally along the convex curved surface 24 from the edge toward the central hole 23. The spiral angle is 15°-30°. 15° is suitable for low-head water pumps, and 30° is suitable for high-head water pumps. Optionally, the cross-section of the lower blade 22 is streamlined to reduce fluid resistance.

[0033] The cover body 11 includes an axial flow hole 13 and an inner concave curved surface 14 that matches the outer convex curved surface 24. The upper blade 12 extends spirally from the edge toward the axial flow hole 13 along the inner concave curved surface 14. The upper blade 12 has the same shape as the lower blade 22. The inner concave curved surface 14 and the outer convex curved surface 24 are arranged opposite each other to form an annular space. The upper blade 12 and the lower blade 22 are arranged alternately and divide the annular flow channel to form multiple curved flow channels. The alternating arrangement of the upper blade 12 and the lower blade 22 can achieve a larger bending angle and a pressurized flow channel, thereby increasing the head of the water pump impeller.

[0034] Both the lower blade 22 and the upper blade 12 have raised reinforcing ribs 15 at their ends. The outer convex surface 24 and the inner concave surface 14 are formed with recessed insertion grooves 25 at the positions corresponding to the raised reinforcing ribs 15. The raised reinforcing ribs 15 and the insertion grooves 25 are connected to each other so that the end of the lower blade 22 can fit with the inner concave surface 14 and the end of the upper blade 12 can fit with the outer convex surface 24.

[0035] Furthermore, at least part of the protruding insert 15 has a recessed expanding curved surface 27 at its end, and the bottom of the insertion groove 25 partially protrudes to form an expanding rib 26, which complements the expanding curved surface 27. When the protruding insert 15 and the insertion groove 25 are inserted into place, the expanding curved surface 27 and the expanding rib 26 abut against each other. Preferably, the expanding curved surface 27 can be set as an arc-shaped groove, a triangular groove, or a trapezoidal groove to increase the contact area between the protruding insert 15 and the insertion groove 25, greatly improving the connection strength. For example, the expanding curved surface 27 can be set as an arc-shaped or parabolic curved surface with a radius of 1 mm to 2 mm; or, the expanding curved surface 27 can be set as a triangular groove with a apex angle of 60° to 90°; or, the expanding curved surface 27 can be set as a trapezoidal groove with an upper base width of 1 mm to 1.5 mm and a lower base width of 2 to 2.5 mm.

[0036] The surface area of ​​the expanded curved surface 27 is larger than the cross-sectional area of ​​the corresponding protruding insert 15, thereby expanding the mating surface area, especially since the insertion groove 25 has a recessed structure. Preferably, the ratio of the surface area of ​​the expanded curved surface 27 to the cross-sectional area of ​​the protruding insert 15 is 1.3-1.5, thereby further improving the mating strength.

[0037] Furthermore, the surface of the raised insert 15 or the insertion groove 25 is provided with welding patterns, which can improve the ultrasonic welding melting effect of the insertion part and enhance the intermolecular bonding force. For example, the surface of the raised insert 15 or the insertion groove 25 is provided with a rough layer to enhance the intermolecular bonding force.

[0038] like Figures 2 to 5 As shown, after the water pump impeller is produced using a mold, it needs to be processed using an ultrasonic device 40. This processing method includes the following steps: Step S101: Align and assemble the bottom shell 10 and top cover 20 to form an assembly; the bottom shell 10 and top cover 20 are injection molded, paired, and the protruding ribs 15 of the lower blade 22 are inserted into the insertion grooves 25 on the concave curved surface 14, while the protruding ribs 15 of the upper blade 12 are inserted into the insertion grooves 25 on the convex curved surface 24, with the lower blade 22 and upper blade 12 alternately arranged. Preferably, alignment can be achieved using positioning auxiliary tooling during assembly.

[0039] In step S102, the water pump impeller is placed on the ultrasonic device 40. The tooling table 50 is provided with an arc-shaped positioning groove 51 that matches the outer curved surface of the bottom shell 10. The bottom shell 10 is a thin-walled structural component. Correspondingly, the outer peripheral wall of the bottom shell 10 is provided with a grooved curved surface. The arc-shaped positioning groove 51 and the grooved curved surface are automatically aligned and supported to improve the positioning accuracy of the grooved curved surface.

[0040] Furthermore, the arc-shaped positioning groove 51 of the tooling table 50 is provided with an elastic buffer pad, which prevents the assembled parts from making hard contact with the tooling table 50 and causing scratches. Preferably, a thick fluororubber buffer layer is embedded in the arc-shaped positioning groove 51, and the thickness of the thick fluororubber buffer layer can be set to 0.3mm-0.5mm. The radius of the arc-shaped positioning groove 51 is basically the same as the outer peripheral wall dimension and part of the bottom wall dimension of the bottom shell 10, so as to accommodate and support the water pump impeller. More preferably, a central protrusion 52 is provided in the middle of the arc-shaped positioning groove 51. The central protrusion 52 is aligned and inserted into the central insert 30 and supports the central hole 23 to provide coaxial central positioning support.

[0041] In step S103, the ultrasonic device 40 is controlled to press down for 1-2 seconds at a pre-pressure of 0.3MPa-0.35MPa to ensure that the upper blade 12 and the convex curved surface 24 are in contact, and the lower blade 22 and the concave curved surface 14 are in contact. The center of the welding head is coaxial with the center hole 23 of the water pump impeller. The welding head is controlled to press down for 1-2 seconds at a pre-pressure of 0.3MPa-0.35MPa to ensure that the upper blade 12 and the convex curved surface 24 of the bottom shell 10, and the lower blade 22 and the concave curved surface of the top cover 20 are in close contact. At the same time, the expansion curved surface 27 and the corresponding expansion rib 26 are in contact with each other, avoiding gaps in the fit and defects in assembly that could affect the welding quality. The pre-pressure step ensures that the alternately distributed upper blade 12 and lower blade 22 can be inserted into place, providing a high-precision foundation for subsequent welding.

[0042] Step S104: Control the ultrasonic equipment 40 to output corresponding welding pressure and welding amplitude, so as to complete the ultrasonic welding of the assembly parts to form a water pump impeller. Adjust the parameters of the ultrasonic equipment 40 to perform ultrasonic welding according to the product characteristics and dimensions. Optionally, start the ultrasonic equipment 40, with the welding head output welding pressure at 0.35 MPa - 0.4 MPa, ultrasonic energy controlled at 110J - 120J, welding time at 0.8 s - 1.2 s, and the welding head amplitude of the ultrasonic equipment 40 at 90%.

[0043] Optionally, the welding head adopts an arc-shaped structure that is compatible with the concave curved surface 14 of the top cover 20, so that the welding energy is evenly transferred to each welding part, and the synchronous welding of the contact parts such as the insert-slot and each blade-curved surface in the water pump impeller is realized.

[0044] More preferably, during the welding process, the ultrasonic equipment 40 monitors the temperature of the welding area in real time through an infrared temperature sensor. The infrared temperature sensor can detect the temperature of the welding part so that the welding temperature of the welding part is maintained at 180℃-220℃, wherein the fluctuation range of the welding temperature is ≤±5℃.

[0045] In one optional embodiment, the welding head has a cooling channel inside, through which circulating cooling water is introduced to prevent the welding head from overheating and causing parameter drift. The cooling channel and cooling water work together to precisely control the temperature change of the welding head.

[0046] In another optional embodiment, the ultrasonic device 40 is equipped with an air-cooling component that delivers cool air toward the welding head to prevent parameter drift caused by overheating of the welding head. The air-cooling component may be configured with a temperature sensor to detect the temperature of the output cool air, so as to flexibly adjust the wind speed and air temperature according to the temperature of the welding area of ​​the welding head, thereby precisely controlling the temperature change of the welding head.

[0047] Step S105: Remove the water pump impeller. Raise the welding head, remove the curved impeller, completing the machining process, and you can proceed to machine the next water pump impeller.

[0048] After the ultrasonic device 40 completes the welding of the water pump impeller in step S104, it is necessary to maintain pressure on the welded water pump impeller to stabilize its shape. The pressure maintained by the ultrasonic device 40 is lower than the welding pressure; preferably, the pressure is between 0.3 MPa and 0.35 MPa, and the pressure maintenance time is 0.8 s to 1.2 s, allowing the welded area of ​​the water pump impeller to cool naturally below the glass transition temperature of the substrate, thus avoiding internal stress caused by excessively rapid cooling.

[0049] The bottom shell 10 and the top cover 20 are interlocked, with the protruding rib 15 and the insertion groove 25 correspondingly interlocked. In one embodiment, the protruding rib 15 includes a lower rib 153 that partially protrudes from the end of the lower blade 22. The lower rib 153 protrudes from the middle of the lower blade 22 to form a long rib structure, thereby increasing the welding length and welding area. Correspondingly, the insertion groove 25 includes a third slot 253 located in the cover body 11, the shape of which is adapted to the shape of the lower rib 153.

[0050] Preferably, the third slot 253 is a groove structure, wherein a second rib 262 is formed at the bottom of the third slot 253, and a first curved surface 271 is formed on the end face of the lower insertion rib 153, the surface area of ​​the first curved surface 271 being larger than the cross-sectional area of ​​the lower insertion rib 153.

[0051] like Figure 2 , Figures 6 to 8 As shown, the insertion groove 25 includes a first slot 251 and a second slot 252 located on the shell body 21. Correspondingly, the protruding insertion rib 15 includes a first insertion rib 151 and a second insertion rib 152 that protrude partially from the end of the upper blade 12. The first insertion rib 151 and the second insertion rib 152 are spaced apart and located at the top two ends of the upper blade 12 respectively to form a two-point welding structure, thereby improving the positioning accuracy of the end of the upper blade 12 so that the end face of the upper blade 12 can accurately fit the convex curved surface 24.

[0052] The first slot 251 and the second slot 252 are spaced apart on the convex curved surface 24. Optionally, both the first slot 251 and the second slot 252 are groove structures. The first slot 251 is adapted to the first insert rib 151, and the second slot 252 is adapted to the second insert rib 152 to increase the welding bonding area. Optionally, the first slot 251 has a through hole structure, and the second slot 252 has a groove structure, so that the first insert rib 151 can be fully inserted into the first slot 251, so that the upper blade 12 and the convex curved surface 24 fit tightly together.

[0053] Furthermore, the expansion rib 26 includes a first rib 261 located in the second slot 252, and the expansion curved surface 27 includes a second curved surface 272 located in the second insert rib 152. The surface area of ​​the second curved surface 272 is larger than the cross-sectional area of ​​the second insert rib 152, resulting in a larger bonding area and enabling multi-point positioning.

[0054] In this embodiment, the projections of the first insert 151, the second insert 152, and the lower insert 153 on the plane perpendicular to the axis are staggered. While maintaining the insertion and positioning connection, the range of welding misalignment is further increased, thereby forming a multi-level staggered welding and fixing structure, improving the bonding strength and maintaining the deformation balance in all directions.

[0055] The ends of the lower insert 153, the first insert 151, and the second insert 152 are all formed with concave expansion surfaces 27, and the corresponding welded surface area is larger than the cross-sectional area of ​​the corresponding insert, which greatly improves the joint strength. Optionally, the expansion surface 27 is 30%-50% larger than the original insert joint area.

[0056] In a preferred embodiment, the thickness of the protruding rib 15 is less than the thickness of the upper blade 12, and a step structure is formed between the protruding rib 15 and the upper blade 12. Therefore, the step surface between the protruding rib 15 and the upper blade 12, the end face of the upper blade 12, the side surface and the end face of the protruding rib 15 are all integrated with the convex curved surface 24 under the action of ultrasonic waves.

[0057] Based on the same principle, the thickness of the protruding rib 15 is less than the thickness of the lower blade 22, and the lower blade 22 and the concave curved surface 14 are integrated into one piece.

[0058] The protruding direction of the raised rib 15 is parallel to the centerline of the axial flow hole 13. The top cover 20 and the bottom shell 10 are assembled by inserting the raised rib 15 into the insertion groove 25 to improve assembly accuracy. The upper blade 12 has a curved surface structure, and the raised rib 15 is located at the top of the upper blade 12 and is parallel to the centerline of the axial flow hole 13. The raised rib 15 and the curved surface of the upper blade 12 form an angle, which can provide multi-directional support force to the curved surface of the upper blade 12, further improving the bonding strength between the upper blade 12 and the bottom shell 10.

[0059] Furthermore, adjacent upper and lower blades at least partially overlap on the projection plane, which is a plane perpendicular to the axis. The partial overlap of the upper and lower blades on the projection plane makes it difficult to machine them in a single step using existing injection molds. Moreover, the partial overlap of the upper and lower blades on the projection plane, close to the axial flow hole, improves the structural strength around the axial flow hole, allowing the pump impeller to withstand greater liquid impact and further increasing the head.

[0060] The pump impeller rotates around the axis of the central hole 23, and the first insert rib 151, the second insert rib 152, and the lower insert rib 153 rotate accordingly, forming rotational trajectories. The rotational areas of the first insert rib 151 and the lower insert rib 153 partially overlap or intersect, as do the rotational areas of the second insert rib 152 and the lower insert rib 153. The rotational area of ​​the first insert rib 151 near the center of the blade partially overlaps or intersects with the rotational area of ​​the lower insert rib 153, and the rotational area of ​​the second insert rib 152 near the center of the blade partially overlaps or intersects with the rotational area of ​​the lower insert rib 153. This creates a cross-support structure when the impeller rotates, enhancing the connection stability between the bottom shell 10 and the top cover 20. Preferably, the overlap between the rotation areas of the first insert 151 and the lower insert 153 is 0-50%, and the overlap between the rotation areas of the second insert 152 and the lower insert 153 is 0-50%. The length of the lower insert 153 is greater than the length of the first insert 151. When the overlap between the rotation areas of the first insert 151 and the lower insert 153 is 0%, their rotation area edges intersect. When the overlap between the rotation areas of the first insert 151 and the lower insert 153 is 50%, half of the rotation area of ​​the first insert 151 intersects with the rotation area of ​​the lower insert 153. The second insert 152 can also be understood in the same way.

[0061] Adjusting the overlap of the rotation area can change the welding and insertion range of the pump impeller, and can also adjust the internal stress to improve rotational stability.

[0062] like Figures 6 to 8 As shown, the upper blade 12 and the lower blade 22 have the same curved surface shape, differing only in the structure of their interlocking parts. The upper blade 12 includes a continuous guide section 121, an extension section 122, and a lifting section 123. The cross-section of the guide section 121 is arc-shaped and protrudes towards the axial flow hole 13, guiding the fluid smoothly into the flow channel and preventing fluid impact on the blades, thus avoiding wear. Optionally, the inlet of the guide section 121 is located within the guide range of the axial flow hole 13. Setting the guide section 121 as an arc-shaped structure enhances its structural strength and provides suitable elastic internal stress, while also reducing noise caused by the impact of the straight wall on the liquid, resulting in good noise reduction. The arc-shaped protrusion of the guide section 121 faces the inlet direction of the axial flow hole 13, and the curved channel follows the rotation direction of the pump impeller, thus enabling a cut-in guiding of the liquid inflow.

[0063] The lifting section 123 intersects at the edge and its end is parallel to the centerline of the axial flow hole 13, which can efficiently push the fluid to the edge of the impeller and increase the pump head. The lifting section 123 has a straight wall structure, and its end intersects with the edge of the pump impeller, forming a tangential liquid outlet structure, which can stabilize the liquid outlet direction and increase the liquid outlet velocity. Preferably, the shell body 21 and the cover body 11 form two relatively parallel planes at the output position of the curved flow channel.

[0064] The extension section 122 connects the lifting section 123 and the drainage section 121. The extension section 122 extends obliquely along the concave curved surface 14, and the angle of inclination matches the curvature of the concave curved surface 14 to ensure a smooth transition of the flow channel. The curved surface of the extension section 122 gradually straightens and smoothly intersects with the arc surface of the drainage section 121 to the lifting section 123, which can both guide the smooth flow of liquid and maintain structural stability.

[0065] Furthermore, the upper blade 12 intersects with the concave curved surface 14. The upper blade 12 gradually bends from the edge of the pump impeller toward the axial flow hole 13. The upper blade 12 is straight at the edge of the pump impeller. The bending angle of the upper blade 12 gradually bends into an arc-shaped surface from the straight edge toward the axial flow hole 13, thereby gradually forming a liquid acceleration and guiding structure and directional output.

[0066] In one embodiment, the curved flow channel has an axial height difference between its inlet at one end of the axial flow hole 13 and its outlet at the edge of the pump impeller, and its cross-sectional area gradually increases from the axial flow hole 13 towards the edge. The shape of the curved flow channel is adjusted according to the shapes of the concave curved surface 14, the convex curved surface 24, the upper blade 12, and the lower blade 22. The curved flow channel has an axial height difference, and the liquid enters from the axial flow hole 13 and exits in a spiral direction, achieving acceleration in both the axial and radial directions, greatly increasing the liquid's outlet velocity and outlet pressure, and thus increasing the head.

[0067] It should be understood that this application is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of this application and include common knowledge or customary techniques in the art that are not disclosed in this invention.

Claims

1. An axial flow booster water pump impeller, the water pump impeller comprising a bottom shell and a top cover coaxially arranged, characterized in that: The bottom shell includes a shell body and at least three evenly distributed lower blades, and the top cover includes a cover body and at least three upper blades; The shell body includes a central hole and an outwardly convex surface that gradually curves and protrudes from the edge toward the central hole. The lower blade extends spirally from the edge toward the central hole along the outwardly convex surface. The cover body includes an axial flow hole and an inwardly concave surface that matches the outwardly convex surface. The upper blade extends spirally from the edge toward the axial flow hole along the inwardly concave surface. The lower blade and the upper blade are alternately arranged and a curved flow channel is formed between them. Both the lower blade and the upper blade have raised inserts at their ends. At least a portion of the raised inserts have recessed expansion surfaces at their ends. The outer and inner convex surfaces have recessed insertion grooves at the positions corresponding to the raised inserts. The bottom of the insertion grooves has raised ribs at their ends. The expansion ribs and the expansion surfaces are complementary. The water pump impeller is welded together as one piece using ultrasonic technology; The protruding insert includes a lower insert forming a partial protrusion from the end of the lower blade, and a first insert and a second insert forming a partial, spaced protrusion from the end of the upper blade. The insertion groove includes a third slot located in the cover body, and a first slot and a second slot located in the shell body. The expansion rib includes a first rib located in the second slot and a second rib located in the third slot. The expansion surface includes a first surface located on the lower insert and a second surface located on the second insert, wherein the surface area of ​​the first surface is greater than the cross-sectional area of ​​the lower insert, and the surface area of ​​the second surface is greater than the cross-sectional area of ​​the second insert. The first slot is adapted to the first insert bar, the second slot is adapted to the second insert bar, and the lower insert bar is adapted to the third slot; The rotation area of ​​the first insert bar and the rotation area of ​​the lower insert bar partially overlap or intersect, and the rotation area of ​​the second insert bar and the rotation area of ​​the lower insert bar partially overlap or intersect.

2. The water pump impeller according to claim 1, characterized in that, The upper and lower blades have the same curved surface shape. The upper blade includes a continuous flow-guiding section, an extension section, and a lifting section. The cross-section of the flow-guiding section is arc-shaped and protrudes towards the axial flow hole. The lifting section intersects at the edge and its end is parallel to the center line of the axial flow hole. The extension section extends obliquely along the concave curved surface.

3. The water pump impeller according to claim 2, characterized in that, The thickness of the protruding rib is less than the thickness of the upper blade.

4. The water pump impeller according to claim 2, characterized in that, The curved flow channel has an axial height difference between its inlet at one end of the axial flow hole and its outlet at the edge of the pump impeller, and its cross-sectional area gradually increases from the axial flow hole toward the edge.

5. The water pump impeller according to claim 1, characterized in that, The expansion surface is an arc-shaped groove, a triangular groove, or a trapezoidal groove.

6. The water pump impeller according to claim 1, characterized in that, The protruding direction of the protruding rib is parallel to the center line of the axial flow hole, and the adjacent upper and lower blades overlap at least partially on the projection plane, wherein the projection plane is a plane perpendicular to the axis.

7. A method for machining a water pump impeller, characterized in that, The method for machining a water pump impeller as described in any one of claims 1 to 6 includes: Align and assemble the bottom shell and top cover to form an assembly; Place the water pump impeller in the ultrasonic device; The ultrasonic device is controlled to press for 1-2 seconds under a pre-pressure of 0.3MPa-0.35MPa to make the upper blade and the outward convex curved surface fit together, and the lower blade and the inward concave curved surface fit together. The ultrasonic equipment is controlled to output corresponding welding pressure and welding amplitude so that ultrasonic welding is completed at the joint of the assembled parts to form a water pump impeller. Remove the water pump impeller.

8. The processing method according to claim 7, characterized in that, The ultrasonic device is controlled to output corresponding welding pressure and welding amplitude, and then: Reduce the pressure of the ultrasonic device to a holding pressure of 0.3 MPa-0.35 MPa; The water pump impeller is subjected to a pressure delay of 0.8 s - 1.2 s to allow the weld to cool naturally to below the glass transition temperature of the substrate.

Images