Electric water pump and its housing assembly

Abstract

This invention provides an electronic water pump and its housing assembly. The housing assembly includes a stator assembly, a rotating shaft, a shaft base, and a molded housing body. The stator assembly is integrally injection molded, and the housing assembly is formed through a secondary injection molding process. The rotating shaft and shaft base are embedded within the molded housing body, and the stator assembly is enclosed within the molded housing body to form a self-sealing seal. The housing assembly of the electronic water pump provided by this invention, by integrally injection molding the stator assembly and then secondary injection molding the stator assembly and housing, achieves a self-sealing effect with the rotor. This eliminates the need for an isolation sleeve between the stator and rotor air gap, reducing housing material costs. It also simplifies the assembly process of the electronic water pump and increases the rigidity of the stator assembly, which is beneficial for reducing noise and improving the reliability of the electronic water pump operation. Therefore, the housing assembly of the electronic water pump described above has significant advantages in terms of installation process, cost, and performance.

Description

Technical Field

[0001] This invention relates to the field of electronic water pump technology, and more specifically, to a housing assembly for an electronic water pump and an electronic water pump including the housing assembly. Background Technology

[0002] Given the prevailing trend of energy conservation, modern high-end cars and electric vehicles mostly use electronic cooling water pumps instead of traditional mechanical water pumps. Compared to traditional water pumps, electronic water pumps offer advantages such as precise control and higher efficiency. Traditional electronic water pumps have the stator mounted in the casing, while the rotor and impeller are located in the hydraulic section. An isolation sleeve exists between the stator and rotor for sealing. Traditional electronic water pumps have many parts, complex assembly, and high costs.

[0003] The related technology discloses a motor structure for an electronic water pump. The stator assembly includes a spindle, armature, rear thrust washer, and stator injection molding layer. The armature, spindle, and rear thrust washer are injection molded into one piece. The stator injection molding layer serves as a motor housing, end cover, and stator isolation sleeve. The stator injection molding layer is a BMC thermosetting molding compound block, which has the following drawbacks: 1) The stator injection molding layer uses a BMC thermosetting molding compound block, which has low strength and cannot meet the strength requirements of the motor housing; 2) The stator injection molding layer has a large volume and a long injection molding time, which can easily damage the windings and other components encased inside the stator injection molding layer; 3) If the stator injection molding layer uses a high-strength PPS material, it will increase the manufacturing cost. Summary of the Invention

[0004] The present invention aims to solve at least one of the above-mentioned technical problems.

[0005] Therefore, the first objective of the present invention is to provide a housing assembly for an electronic water pump.

[0006] A second aspect of the present invention is to provide an electronic water pump including the aforementioned housing assembly.

[0007] To achieve the above objectives, the present invention provides a housing assembly for an electronic water pump. The housing assembly includes a stator assembly, a rotating shaft, a shaft base, and a housing injection molded body. The stator assembly is integrally injection molded, and the housing assembly is formed by secondary injection molding. The rotating shaft and the shaft base are both embedded inside the housing injection molded body, and the stator assembly is enclosed inside the housing injection molded body to form a self-sealing seal.

[0008] The electronic water pump housing assembly provided by the above-mentioned technical solution of the present invention is formed by integral injection molding of the stator assembly, and then the stator assembly and housing are injection molded in a second stage, achieving a self-sealing effect with the rotor. This eliminates the need for the isolation sleeve between the stator and rotor air gap, reduces the material cost of the housing, simplifies the assembly process of the electronic water pump, and improves the rigidity of the stator assembly, which is beneficial to the reduction of noise in the electronic water pump and improves the reliability of the electronic water pump operation. Therefore, the electronic water pump housing assembly of the above-mentioned solution has significant advantages in terms of installation process, cost, and performance.

[0009] Secondly, the stator assembly is first injection molded as a whole, and then the housing assembly is injection molded in a second stage. This allows the stator injection body of the stator assembly and the housing injection body of the housing assembly to use different injection molding materials. The housing injection body requires high strength and can use a more expensive injection molding material, while the stator injection body requires low strength and can use a less expensive injection molding material. Compared with related technologies where the stator injection layer is used as the motor housing, the above solution ensures the strength of the housing injection body while saving material costs. Thirdly, injection molding the stator injection body and the housing injection body separately results in a smaller stator injection body volume and a shorter injection molding time. The injection molding of the stator injection body will not damage the windings and other components inside the stator injection body, thereby ensuring the reliability of the electronic water pump.

[0010] In addition, the housing assembly of the electronic water pump provided in the above-described technical solution of the present invention may also have the following additional technical features:

[0011] In the above technical solution, preferably, the stator assembly includes a pin, a winding, an insulating frame, a stator core, and a stator injection molded body. The insulating frame wraps around the stator core, the winding is wound around the teeth of the insulating frame, the pin is fixed in the groove of the insulating frame, and the stator injection molded body tightly wraps and secures the pin, the winding, the insulating frame, and the stator core.

[0012] The stator assembly is encapsulated and secured by a stator injection molded body, thereby injection molding the entire stator assembly into one piece.

[0013] In the above technical solution, preferably, the stator assembly includes a stator injection molded body, the stator injection molded body is a thermosetting material, and the curing deformation temperature of the thermosetting material is not lower than the injection temperature of the housing injection molded body.

[0014] The stator injection body is made of thermosetting material, preferably BMC thermosetting material, which has low material cost; the curing deformation temperature of the thermosetting material is not lower than the injection temperature of the housing injection body, so as to avoid the risk of melting the stator injection body formed in one injection during the secondary injection molding of the housing components.

[0015] In the above technical solution, preferably, the stator assembly includes a stator injection molded body, the stator injection molded body is a thermosetting material, and the housing injection molded body is a PPS material.

[0016] The stator injection body uses low-cost thermosetting materials, preferably BMC thermosetting materials, while the housing injection body uses high-strength PPS materials, which ensures the strength of the housing injection body while saving material costs.

[0017] The second aspect of the present invention provides an electronic water pump, including a hydraulic section, a brushless motor section, and a control section. The hydraulic section includes a pump casing and an impeller. The brushless motor section includes a rotor and a housing assembly as described in any of the above technical solutions. The control section includes a control board and a rear end cover. The brushless motor section is installed between the hydraulic section and the control section.

[0018] The electronic water pump provided by the above-described technical solutions of the present invention, because it includes the housing assembly of any of the above-described technical solutions, has the beneficial effects of the housing assembly of any of the above-described technical solutions.

[0019] In the above technical solution, preferably, the impeller and the rotor are integrally injection molded to form an impeller-rotor assembly.

[0020] The impeller of the hydraulic section and the rotor of the brushless motor section are integrally injection molded and installed inside the pump casing and the machine casing respectively, which makes the impeller rotor assembly easy to manufacture and low in cost.

[0021] In the above technical solution, preferably, the impeller includes an impeller body and blades, the rotor includes a rotor core, magnets and a bushing, the rotor core is provided with a magnet slot, the magnet is installed in the magnet slot, the rotor core and the magnet are plastic-encapsulated inside the impeller body to form impeller rotor assembly one, and the bushing is secondary injection molded in impeller rotor assembly one to form impeller rotor assembly two.

[0022] The impeller rotor assembly described above comprises two parts: an impeller and a rotor. The impeller includes an impeller body and blades; the rotor includes an iron core, magnets, and a bushing. The impeller rotor assembly is formed through a two-step injection molding process. The first step is to injection mold the impeller body, and the second step is to injection mold the bushing. This allows the injection molding materials used for the impeller body and the bushing to be different. The material requirements for the injection-molded impeller body are high strength and acid / alkali resistance, while the material requirements for the injection-molded bushing are wear-resistant, high strength, and acid / alkali resistance. The material cost for the injection-molded bushing is higher than that for the injection-molded impeller body. Firstly, it has lower manufacturing costs compared to impeller rotor assemblies where the bushing and impeller body are injection molded as a single unit. Secondly, the iron core and magnets are encapsulated within the impeller body, ensuring a strong bond. The bushing is small in size and lightweight, resulting in low torque on the bushing during impeller rotor assembly rotation, making it less prone to slippage. Thirdly, the large impeller body and small bushing allow for faster injection molding of the bushing, preventing any impact on the impeller rotor assembly. This means that the first injection-molded impeller body will not melt during the secondary injection molding of the bushing, thus effectively avoiding the risk of iron core and magnet displacement.

[0023] In the above technical solution, preferably, the blade is an injection molded body, and the impeller rotor assembly II is ultrasonically welded to the blade.

[0024] The impeller is formed by ultrasonic welding, which integrates the blades and the impeller rotor assembly. The injection mold for integral injection molding of the impeller is complex and has high maintenance costs. Therefore, the impeller is divided into two parts, the impeller body and the blades, which are injection molded separately and then ultrasonically welded. This simplifies the structure of the injection mold and greatly reduces the maintenance costs of the injection mold.

[0025] In any of the above technical solutions, preferably, a first sealing ring is installed between the front end of the housing injection body of the housing assembly and the pump housing to form a closed hydraulic cavity; a second sealing ring is installed between the rear end of the housing injection body of the housing assembly and the rear end cover to form a closed electrical control cavity.

[0026] The control board of the control unit is installed inside the electrical control cavity formed by the housing and the rear end cover. The brushless motor unit is installed between the water conservancy unit and the control unit. The stator assembly of the brushless motor unit is integrally injection molded and then injection molded with the housing. Sealing rings are installed between the housing of the brushless motor unit and the pump housing, and between the housing of the brushless motor unit and the rear end cover, to achieve the sealing of the electronic water pump.

[0027] In any of the above technical solutions, preferably, the hydraulic part and the brushless motor part are fixedly connected by screws, and the brushless motor part and the control part are fixedly connected by screws, which makes assembly convenient and the connection firm.

[0028] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0029] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0030] Figure 1 This is a cross-sectional view of a stator assembly according to an embodiment of the present invention;

[0031] Figure 2 This is a cross-sectional structural schematic diagram of a housing assembly according to an embodiment of the present invention;

[0032] Figure 3 This is a cross-sectional structural schematic diagram of an electronic water pump according to an embodiment of the present invention;

[0033] Figure 4 This is a cross-sectional structural schematic diagram of an impeller rotor assembly according to an embodiment of the present invention.

[0034] in, Figures 1 to 4 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0035] 1. Housing assembly, 11. Stator assembly, 111. Pin, 112. Winding, 113. Stator core, 114. Stator injection molded body, 115. Insulating frame, 12. Shaft, 13. Shaft base, 14. Housing injection molded body, 2. Pump housing, 3. Impeller rotor assembly, 31. Shaft sleeve, 32. Magnet, 33. Rotor core, 34. Impeller body, 35. Blade, 4. First sealing ring, 5. Second sealing ring, 6. Control board, 7. Rear end cover. Detailed Implementation

[0036] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0037] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0038] The following reference Figures 1 to 4 This invention describes an electronic water pump and its housing assembly according to some embodiments of the present invention.

[0039] like Figure 2 and Figure 3As shown, according to some embodiments of the present invention, an electronic water pump housing assembly 1 includes a stator assembly 11, a rotating shaft 12, a shaft base 13, and a housing injection molded body 14. The stator assembly 11 is integrally injection molded, and the housing assembly 1 is formed by secondary injection molding. The rotating shaft 12 and the shaft base 13 are interference-fitted. Both the rotating shaft 12 and the shaft base 13 are embedded inside the housing injection molded body 14. The stator assembly 11 is wrapped inside the housing injection molded body 14 to form a self-sealing structure.

[0040] The housing assembly 1 of the electronic water pump provided in the above embodiments of the present invention is formed by integral injection molding of the stator assembly 11, and then the stator assembly 11 and the housing are injection molded in a second time, achieving a self-sealing effect with the rotor. This eliminates the need for the isolation sleeve between the stator and rotor air gap, reduces the material cost of the housing, simplifies the assembly process of the electronic water pump, and increases the rigidity of the stator assembly 11, which is beneficial to the reduction of noise in the electronic water pump and improves the reliability of the electronic water pump operation. Therefore, the housing assembly 1 of the electronic water pump in the above-mentioned solution has obvious advantages in terms of installation process, cost and performance.

[0041] Secondly, the stator assembly 11 is first injection molded as a whole, and then the housing assembly 1 is injection molded in a second step. In this way, the stator injection body 114 of the stator assembly 11 and the housing injection body 14 of the housing assembly 1 can be made of different injection molding materials. The housing injection body 14 requires high strength and can use higher-cost injection molding materials, while the stator injection body 114 requires low strength and can use lower-cost injection molding materials. Compared with the stator injection layer as the motor housing in related technologies, the above solution not only ensures the strength of the housing injection body 14, but also saves material costs. Thirdly, the stator injection body 114 and the housing injection body 14 are injection molded separately, which makes the volume of the stator injection body 114 smaller and the injection molding time shorter. The injection molding of the stator injection body 114 will not damage the internal components such as the winding 112 of the stator injection body 114, thereby ensuring the performance reliability of the electronic water pump.

[0042] In one embodiment of the present invention, such as Figure 1 As shown, the stator assembly 11 includes a pin 111, a winding 112, an insulating frame 115, a stator core 113, and a stator injection molded body 114. The insulating frame 115 encloses the stator core 113, the winding 112 is wound around the teeth of the insulating frame 115, the pin 111 is fixed in the groove of the insulating frame 115, and the stator injection molded body 114 encloses and secures the pin 111, the winding 112, the insulating frame 115, and the stator core 113. The stator injection molded body 114 encloses and secures the entire component of the stator assembly 11, thereby injection molding the stator assembly 11 as a whole.

[0043] Preferably, the stator assembly 11 includes a stator injection molded body 114, which is a thermosetting material, and the curing deformation temperature of the thermosetting material is not lower than the injection temperature of the housing injection molded body 14.

[0044] The stator injection body 114 is made of thermosetting material, preferably BMC thermosetting material, which has low material cost; the curing deformation temperature of the thermosetting material is not lower than the injection temperature of the housing injection body 14, so as to avoid the risk of melting the stator injection body 114 formed by one injection during the secondary injection molding of the housing assembly 1.

[0045] Preferably, the stator assembly 11 includes a stator injection molded body 114, which is made of thermosetting material, and the housing injection molded body 14 is made of PPS material.

[0046] The stator injection body 114 is made of a low-cost thermosetting material, preferably BMC thermosetting material, while the housing injection body 14 is made of a high-strength PPS material, which ensures the strength of the housing injection body 14 and saves material costs.

[0047] like Figure 3 As shown, an embodiment of the second aspect of the present invention provides an electronic water pump, including a hydraulic section, a brushless motor section, and a control section. The hydraulic section includes a pump housing 2 and an impeller; the brushless motor section includes a rotor and a housing assembly 1 as described in any of the above embodiments; the control section includes a control board 6 and a rear end cover 7; the brushless motor section is installed between the hydraulic section and the control section.

[0048] The electronic water pump provided in the above embodiments of the present invention has the beneficial effects of the housing assembly 1 of any of the above embodiments because it includes the housing assembly 1 of any of the above embodiments, which will not be repeated here.

[0049] Preferably, such as Figure 3 and Figure 4 As shown, the impeller and rotor are integrally injection molded to form the impeller-rotor assembly 3.

[0050] The impeller of the hydraulic part and the rotor of the brushless motor part are integrally injection molded and installed in the pump casing 2 and the machine casing respectively, which makes the impeller rotor assembly 3 easy to manufacture and low in cost.

[0051] In one embodiment of the present invention, such as Figure 4 As shown, the impeller includes an impeller body 34 and blades 35, and the rotor includes a rotor core 33, magnets 32 and a bushing 31. The rotor core 33 is provided with a magnet 32 ​​slot, and the magnets 32 are installed in the magnet 32 ​​slot. The rotor core 33 and the magnets 32 are encapsulated inside the impeller body 34 to form impeller rotor assembly one. The bushing 31 is injection molded into impeller rotor assembly one to form impeller rotor assembly two.

[0052] The impeller rotor assembly 3 described above comprises two parts: an impeller and a rotor. The impeller includes an impeller body 34 and blades 35; the rotor includes a rotor core 33, magnets 32, and a bushing 31. The impeller rotor assembly 3 is formed through a two-step injection molding process. The first step is to injection mold the impeller body 34, and the second step is to injection mold the bushing 31. Thus, the injection molding materials used for the impeller body 34 and the bushing 31 can be different. The material requirements for the injection molded impeller body 34 are high strength and acid / alkali resistance, while the material requirements for the injection molded bushing 31 are wear-resistant, high strength, and acid / alkali resistance. The material used for the injection molded bushing 31 is more expensive than the material used for the injection molded impeller body 34. The cost is low, saving manufacturing costs compared to the impeller rotor assembly 3, which is integrally injection molded with the bushing 31 and the impeller body 34. Secondly, the iron core and magnet 32 ​​are encapsulated in the impeller body 34 and are firmly bonded. The bushing 31 is small in size and light in weight, and the torque that drives the bushing 31 to rotate when the impeller rotor assembly 3 rotates is small, so the bushing 31 is not easy to slip. Thirdly, the impeller body 34 is large in size and the bushing 31 is small in size, so the injection molding speed of the bushing 31 is fast and will not affect the impeller rotor assembly. That is, the impeller body that was first injection molded will not melt during the secondary injection molding of the bushing 31, thus effectively avoiding the risk of displacement of the iron core and magnet 32.

[0053] Furthermore, such as Figure 4 As shown, blade 35 is an injection molded body, and impeller rotor assembly 2 and blade 35 are welded together by ultrasonic welding.

[0054] The impeller is formed by ultrasonic welding, where the blades 35 and the impeller rotor assembly are welded together by ultrasonic welding. The injection mold structure for integral injection molding of the impeller is complex and has high maintenance costs. Therefore, the impeller is divided into two parts, the impeller body 34 and the blades 35, which are injection molded separately. Weld lines are provided on the blades 35 and welding grooves are provided on the impeller body 34. The impeller is then formed by ultrasonic welding. The structure of the injection mold is simple, which greatly reduces the maintenance cost of the injection mold.

[0055] Specifically, a first sealing ring 4 is installed between the front end of the injection molded body 14 of the housing assembly 1 and the pump housing 2 to form a closed hydraulic cavity; a second sealing ring 5 is installed between the rear end of the injection molded body 14 of the housing assembly 1 and the rear end cover 7 to form a closed electrical control cavity.

[0056] The control board 6 of the control unit is installed inside the electrical control cavity formed by the housing and the rear cover 7. The brushless motor unit is installed between the water conservancy unit and the control unit. The stator assembly 11 of the brushless motor unit is integrally injection molded and then injection molded with the housing. Sealing rings are installed between the housing of the brushless motor unit and the pump housing 2, and between the housing of the brushless motor unit and the rear cover 7, respectively, to achieve the sealing of the electronic water pump.

[0057] Preferably, the hydraulic unit and the brushless motor unit are fixedly connected by screws, and the brushless motor unit and the control unit are fixedly connected by screws, which makes assembly convenient and the connection firm.

[0058] In one specific embodiment, such as Figure 3 As shown, the electronic water pump includes a hydraulic section, a brushless motor section, and a control section. The impeller of the hydraulic section and the rotor of the brushless motor section are integrally injection molded and are respectively installed inside the pump housing 2 and the machine housing. The control board 6 of the control section is installed inside the electrical control cavity formed by the machine housing and the rear end cover 7, and the brushless motor section is installed between the hydraulic section and the control section. The stator assembly 11 of the brushless motor section is integrally injection molded and then injection molded with the machine housing. Sealing rings are installed between the machine housing of the brushless motor section and the pump housing 2, and between the machine housing of the brushless motor section and the rear end cover 7, to achieve the sealing of the electronic water pump. The above solution utilizes the integral injection molding technology of the stator and the machine housing, which not only saves the material cost of the traditional electronic water pump machine housing, but also eliminates the isolation sleeve between the stator and rotor air gap, and simplifies the installation process of the electronic water pump. In addition, the increase in stator rigidity is also conducive to the improvement of the noise of the electronic water pump. Therefore, the above solution has significant advantages in terms of installation process, cost, and performance.

[0059] Specifically, the electronic water pump is a vehicle-mounted electronic water pump.

[0060] In the description of this invention, it should be understood that the terms "inner" and "outer," etc., 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 this invention and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0061] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," "fixed," etc., should be interpreted broadly. For example, "connected" can be a fixed connection, a detachable connection, an integral connection, or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0062] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An electronic water pump, characterized in that, The electronic water pump includes a hydraulic section and a brushless motor section. The hydraulic section includes a pump casing and an impeller. The brushless motor section includes a rotor and a housing assembly. The housing assembly includes a stator assembly, a rotating shaft, a shaft base, and a housing injection molded body. The stator assembly is integrally injection molded, and the housing assembly is integrally injection molded. The rotating shaft and the shaft base are both embedded inside the housing injection molded body, and the stator assembly is wrapped inside the housing injection molded body to form a self-sealing structure. The stator assembly includes a stator injection molded body, and the strength of the housing injection molded body is greater than the strength of the stator injection molded body; The stator injection body is made of thermosetting material, and the curing deformation temperature of the thermosetting material is not lower than the injection temperature of the housing injection body; The impeller and the rotor are integrally injection molded to form an impeller-rotor assembly; The impeller includes an impeller body and blades, and the rotor includes a rotor core, magnets and a bushing. The rotor core is provided with a magnet slot, and the magnets are installed in the magnet slots. The rotor core and the magnets are encapsulated inside the impeller body to form an impeller rotor assembly one. The bushing is injection molded into the impeller rotor assembly one to form an impeller rotor assembly two. The impeller body and the bushing are each injection molded with different injection molding materials. The bushing has radially extending flanges at both ends.

2. The electronic water pump according to claim 1, characterized in that, The stator assembly further includes pins, windings, an insulating frame, and a stator core. The insulating frame encloses the stator core, the windings are wound around the teeth of the insulating frame, the pins are fixed in the grooves of the insulating frame, and the stator injection molded body tightly encloses and secures the pins, the windings, the insulating frame, and the stator core.

3. The electronic water pump according to claim 1 or 2, characterized in that, The injection-molded housing is made of PPS material.

4. The electronic water pump according to claim 1, characterized in that, Also includes: The control unit includes a control panel and a rear end cover; The brushless motor unit is installed between the hydraulic unit and the control unit.

5. The electronic water pump according to claim 1, characterized in that, The blade is an injection molded body, and the impeller rotor assembly II is ultrasonically welded to the blade.

6. The electronic water pump according to claim 4, characterized in that, A first sealing ring is installed between the front end of the housing injection body of the housing assembly and the pump housing to form a closed hydraulic cavity; A second sealing ring is installed between the rear end of the injection-molded housing body of the housing assembly and the rear end cover to form a sealed electronic control cavity.

7. The electronic water pump according to claim 4, characterized in that, The hydraulic unit and the brushless motor unit are fixedly connected by screws, and the brushless motor unit and the control unit are fixedly connected by screws.

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