Rotor assembly for electronic water pump and electronic water pump

Abstract

The utility model relates to the technical field of electronic water pumps of automobiles, and discloses a rotor assembly for an electronic water pump and the electronic water pump, which comprises a rotor iron core and magnetic steel inserted in the rotor iron core, the rotor iron core and the magnetic steel are arranged in the pre-wrapping shell in an injection molding mode, and through holes used for being aligned with the magnetic steel are formed in the end face of the pre-wrapping shell. The impeller assembly and the pre-wrapping shell are formed into a whole through secondary injection molding, so that the end face of the end, provided with the through hole, of the pre-wrapping shell corresponds to the shoulder on the impeller assembly; sealing is formed between the pre-wrapping shell and the shoulder through an annular boss and an annular groove which are formed in the pre-wrapping shell and the shoulder, the through hole is surrounded on the inner sides of the annular boss and the annular groove, and the annular boss and the annular groove are correspondingly attached. The rotor assembly has the technical effects that the pulling-out force is obviously improved, the thermal expansion resistance is realized, cooling liquid is difficult to enter the rotor iron core, and the performance of the rotor assembly is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic water pumps for automobiles, in particular to a rotor assembly for electronic water pumps and an electronic water pump. Background Art

[0002] New energy vehicles, RVs and other special vehicles often use micro water pumps as water circulation, cooling or on-board water supply systems. This type of micro self-priming water pump is collectively referred to as an automotive electronic water pump.

[0003] The automotive electronic water pump in current technology generally consists of the following components: a casing as a working space, in which a stator assembly, a rotor assembly, a rotating shaft and an impeller assembly are integrated, wherein the rotor assembly can rotate in response to the magnetic field between the stator assembly and the rotor assembly, and the impeller assembly is driven by the rotor assembly to rotate to realize the operation of the impeller assembly, and the rotating shaft is used to guide the movement of the rotor assembly.

[0004] Generally, the rotor assembly and the impeller assembly are injection molded as a whole and sleeved on the rotating shaft. During the production, the magnetic steel is first inserted into the rotor core, and then the pre-package shell is injection molded on the outside of the two. After molding, the magnetic steel, the rotor core, and the pre-package shell are taken as a whole, and the impeller assembly is obtained by secondary injection molding on the outside;

[0005] During the two injection molding processes, since the pre-package shell needs to be positioned with the magnetic steel, a positioning convex is reserved on the injection mold. After injection molding, a through groove is formed at a position corresponding to the positioning convex on the pre-package shell. In order to prevent the coolant in the water pump from entering the rotor core, the existing method is to form a column convex on the impeller assembly to close the through groove during the secondary injection molding.

[0006] However, when the water pump operates under high temperature conditions, the injection molded parts will expand, and a pull-off force will be generated under the action of the expansion. This pull-off force makes it impossible to completely prevent the coolant from penetrating into the rotor core by the sealing effect of the column convex alone, which will result in the performance of the electronic water pump cannot be guaranteed. Utility Model Content

[0007] Based on the above defects, the utility model proposes to add a structure that can enhance the pull-out resistance in the double injection molding structure of the rotor assembly and the impeller assembly, so as to prevent the coolant from entering the rotor core through the groove when thermal expansion occurs, thereby improving the performance of the electronic water pump.

[0008] Specifically, the utility model provides a rotor assembly for an electronic water pump, wherein the rotor of the rotor assembly includes an iron core and a magnet inserted in the rotor core; further includes a pre-package shell in which the rotor core and the magnet are injection-molded, and a through hole is formed on the end face of the pre-package shell for aligning with the magnet; further includes an impeller assembly, which is formed as a whole with the pre-package shell by secondary injection molding, so that an end face of the pre-package shell with the through hole corresponds to a shoulder on the impeller assembly.

[0009] Different from the traditional structure, a seal is formed between the pre-package shell and the shoulder through an annular boss and an annular groove formed thereon, wherein the through hole is surrounded by the inner side of the annular boss and the annular groove, and the annular boss and the annular groove are correspondingly fitted, and the annular boss and the annular groove together form a second seal. Moreover, because it is annular, the pull-off force between the pre-package shell and the impeller assembly is significantly improved, thereby counteracting the effect of thermal expansion, making it difficult for the coolant to enter the rotor core from all directions.

[0010] Preferably, the annular boss is formed by protruding from the end surface of the pre-package shell, and correspondingly, the annular groove is formed by being recessed in the shoulder; or, the annular boss is formed by protruding from the shoulder, and correspondingly, the annular groove is formed by being recessed in the end surface of the pre-package shell;

[0011] That is, the annular boss and the annular groove are formed on the end faces of the pre-package shell and the impeller assembly, so that the two do not need to occupy additional water pump space during secondary injection molding.

[0012] Preferably, in order to further enhance the pull-off resistance, the annular boss is formed by connecting a plurality of arc segments concave toward the inner side of the annular boss and a plurality of arc segments convex toward the inner side of the annular boss, that is, the serpentine annular structure can achieve a function similar to a labyrinth seal.

[0013] Preferably, in order to further enhance the anti-pull-off force, a plurality of arc segments concave toward the inner side of the annular boss and a plurality of arc segments convex toward the inner side of the annular boss are arranged at intervals.

[0014] Preferably, a columnar boss is formed on the shoulder for being placed in the through hole to position and seal the through hole. The columnar boss is formed during secondary injection molding to block the through hole.

[0015] The utility model also provides an electronic water pump, which comprises the rotor assembly for the electronic water pump mentioned above. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0017] Figure 1It is a three-dimensional diagram of a rotor assembly for an electronic water pump in an embodiment of the utility model;

[0018] Figure 2 It is a perspective view of a rotor assembly for an electronic water pump in an embodiment of the utility model;

[0019] In the figure:

[0020] Rotor core 1;

[0021] Magnetic steel 2;

[0022] Pre-package shell 3, through hole 31, annular groove 32;

[0023] Impeller assembly 4 , shoulder 41 , annular boss 42 , columnar boss 43 , impeller 44 , shaft 45 . DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0025] Example: Figure 1 This embodiment provides an optimal implementation scheme for a rotor assembly for an electronic water pump, which is used in the electronic water pump to generate excitation with the stator assembly in the electronic water pump to rotate, and convert the rotational force into power of the water body to increase the pressure of the water body.

[0026] Specifically, Figure 2 The rotor assembly includes a rotor core 1 and a magnet 2 inserted in the rotor core 1. In the present embodiment, there are four rotor cores 1 in a square plate-like structure, which are inserted in the cylindrical magnet 2. The rotor core 1 and the magnet 2 both follow the structure of a traditional electronic water pump.

[0027] Further, such as Figure 2 The rotor assembly also includes a pre-encapsulated shell 3 in which the rotor core 1 and the magnetic steel 2 are injection-molded. The pre-encapsulated shell 3 is cylindrical with both ends closed. A through hole 31 is formed on the end surface of the pre-encapsulated shell 3 for aligning with the magnetic steel 2. The through hole is formed when the pre-encapsulated shell 3 is injection-molded.

[0028] Further, such as Figure 2The rotor assembly also includes an impeller assembly 4, which is formed as a whole with the pre-package shell 3 by secondary injection molding, so that the end surface of the pre-package shell 3 with a through hole 31 corresponds to the shoulder 41 on the impeller assembly 4, and the impeller assembly 4 includes an integrally injection-molded impeller 44 and a shaft body 45. The shoulder 41 is formed at one end of the shaft body 45 away from the impeller 44, so that the pre-package shell 3, the shaft body 45 and the shoulder 41 are formed into an integrated structure during the secondary injection molding, and the bearing is simultaneously injected into the shaft body 45 during the secondary injection molding to facilitate the subsequent assembly of the rotor assembly and the rotating shaft of the water pump.

[0029] Furthermore, unlike the rotor assembly in a conventional electronic water pump, Figure 2 In the present rotor assembly, a seal is formed between the pre-pack shell 3 and the shoulder 41 by means of an annular boss 32 and an annular groove 42 formed thereon, wherein the through hole 31 is surrounded by the inner side of the annular boss 32 and the annular groove 42, and the annular boss 32 and the annular groove 42 are correspondingly fitted. The annular boss 32 and the annular groove 42 not only provide a sealing effect but also increase the anti-pull-off force, thereby preventing the water pump from thermally expanding and causing the sealing performance to decrease when running at a higher temperature.

[0030] Furthermore, in this embodiment, if Figure 2 , the annular boss 32 protrudes from the shoulder 41, and correspondingly, the annular groove 42 is recessed in the end surface of the pre-package shell 3; in other embodiments, the annular boss 32 can also be protruded from the end surface of the pre-package shell 3, and correspondingly, the annular groove 42 is recessed in the shoulder 41.

[0031] Furthermore, in this embodiment, if Figure 2 The annular boss 32 is formed by connecting a plurality of arc segments concave toward the inner side of the annular boss 32 and a plurality of arc segments convex toward the inner side of the annular boss 32. The connected arc segments are beneficial to increase the anti-pull-off force.

[0032] Furthermore, in this embodiment, if Figure 2 A plurality of arc segments concave toward the inner side of the annular boss 32 and a plurality of arc segments convex toward the inner side of the annular boss 32 are arranged at intervals, so that when the rotor assembly is used in an electronic water pump, the adaptable medium temperature range is increased to ≤120°C, which is 30°C higher than the ≤90°C of the traditional rotor assembly, and has a better performance technical effect.

[0033] Further, such as Figure 2 A columnar boss 43 is formed on the shoulder 41 for being placed in the through hole 31 to position and seal the through hole 31 .

[0034] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0035] Finally, it should be noted that the above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A rotor assembly for an electronic water pump, comprising: A rotor core and a magnetic steel inserted in the rotor core; and a pre-enclosed shell in which the rotor core and the magnetic steel are injection-molded, wherein an end surface of the pre-enclosed shell is formed with a through hole for aligning with the magnetic steel; and an impeller assembly, wherein the impeller assembly and the pre-package shell are formed as one body by secondary injection molding, so that an end surface of the pre-package shell having a through hole corresponds to a shoulder on the impeller assembly; Features: The pre-package shell and the shoulder are sealed by an annular boss and an annular groove formed thereon, wherein the through hole is surrounded by the inner sides of the annular boss and the annular groove, and the annular boss and the annular groove are correspondingly fitted.

2. The rotor assembly for an electronic water pump according to claim 1, characterized in that: The annular boss is formed by protruding from the end surface of the pre-package shell, and correspondingly, the annular groove is formed by being recessed in the shoulder; Alternatively, the annular boss is formed by protruding from the shoulder, and correspondingly, the annular groove is formed by being recessed into the end surface of the pre-package shell.

3. The rotor assembly for an electronic water pump according to claim 2, characterized in that: The annular boss is formed by connecting a plurality of arc segments concave toward the inner side of the annular boss and a plurality of arc segments convex toward the inner side of the annular boss.

4. The rotor assembly for an electronic water pump according to claim 3, characterized in that: A plurality of arc segments concave toward the inner side of the annular boss and a plurality of arc segments convex toward the inner side of the annular boss are arranged at intervals.

5. A rotor assembly for an electronic water pump according to any one of claims 1 to 4, characterized in that: The shoulder is formed with a columnar boss for being placed in the through hole to position and seal the through hole.

6. An electronic water pump, characterized in that: A rotor assembly for an electronic water pump comprising the rotor assembly as claimed in any one of claims 1 to 5.

Images