Shaft limiting assembly and rotor assembly and electronic water pump using same

Abstract

The utility model discloses a limiting assembly, a rotor assembly using the limiting assembly and an electronic water pump. The limiting assembly comprises an annular fixing sleeve with a central through hole and an annular gasket which is suitable for being partially embedded in the central through hole and is provided with a shaft hole. A plurality of limiting structures which are in concave-convex fit are arranged on the matching surface of the central through hole and the annular gasket at intervals in the circumferential direction; and an anti-falling structure suitable for axial abutting is further arranged between the annular fixing sleeve and the annular gasket. The reliable stability of the electronic water pump in the long-term use process can be improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to water pump technical field especially relates to a kind of shaft limiting assembly and rotor assembly and electronic water pump using it. BACKGROUND

[0002] Water pump is the mechanical of conveying liquid or making liquid pressure increase. It transmits the mechanical energy of prime mover or other external energy to liquid, and makes liquid energy increase. In the process of water pump operation, rotor rotates to drive impeller to run, in order to ensure that water pump water conservancy performance is reliable and stable, it needs to prevent axial movement during the rotation of rotor, so that the rotor core and stator core of motor are aligned in axial direction, so as to ensure that the magnetic leakage of magnet is minimum, and then ensure that the use performance of motor structure in water pump is good. In addition, if axial movement during the rotation of rotor cannot be effectively prevented, it will also cause the impeller at the shaft head end and water pump shell to collide, which will affect the normal work of water pump and even shorten the service life.

[0003] Based on the above situation, the publication number CN220421521U discloses a rotor assembly and a water pump using the same, which is provided with a cover plate at each of the two axial side ends of the rotor core of the rotor assembly, and a limiting assembly is arranged at the side end of each cover plate away from the bracket. The limiting assembly comprises a limiting pad connected with the cover plate and a wear-resistant pad embedded in the limiting pad. The wear-resistant pad is made of ceramic material, and the limiting pad is made of rubber material. The limiting pad wraps the wear-resistant pad by injection molding, so that the limiting pad and the wear-resistant pad form a combined body to realize the assembly and fixation with the cover plate. The limiting pad enables the limiting assembly to have a certain elasticity to facilitate the assembly and fixation with the cover plate, and the wear-resistant pad enables the limiting assembly to have a certain structural strength.

[0004] For the limiting assembly described above, although the injection molding wrapping method can improve the integration of the limiting pad and the ceramic pad, the injection molding method increases the processing procedure, which in turn increases the production cost. In addition, in order to meet the use requirements of the injection molding processing method, the limiting pad is made of rubber material. The limiting pad made of this material may accelerate aging due to long-term contact with the liquid circulating in the electronic water pump.

[0005] Based on the problems of the limiting assembly applied to the rotor assembly of the water pump in the prior art, the overall structure needs to be further optimized. UTILITY MODEL CONTENTS

[0006] The first object of the utility model is to provide a kind of shaft limiting assembly, to solve the technical problems of improving the reliability and stability in long-term use state.

[0007] The second purpose of the utility model is to provide a rotor assembly to solve the technical problem of improving the reliability and stability of the shaft limiting assembly in long-term use.

[0008] The third purpose of the utility model is to provide an electronic water pump to solve the technical problem of improving the reliability and stability of the rotor assembly in long-term use.

[0009] The shaft limiting assembly is implemented as follows:

[0010] A shaft limiting assembly comprises an annular fixing sleeve with a central through hole and an annular gasket with a shaft hole embedded in the central through hole; wherein

[0011] The central through hole and the annular gasket are provided with a plurality of limiting structures in concave-convex cooperation in the circumferential direction.

[0012] The annular fixing sleeve and the annular gasket are further provided with anti-disengagement structures adapted to axially abut.

[0013] In the optional implementation of the utility model, the limiting structures comprise a plurality of bosses distributed in the circumferential direction on the inner wall surface of the central through hole, and a plurality of grooves on the outer circular wall surface of the annular gasket adapted to one-to-one cooperation with the plurality of bosses.

[0014] In the optional implementation of the utility model, the annular fixing sleeve comprises an annular body for forming the central through hole, and an annular extension provided on one shaft side end of the annular body and extending to the side of the shaft center of the central through hole.

[0015] In the optional implementation of the utility model, the annular gasket comprises a gasket body with a shaft hole and an annular flange connected to one shaft side end of the gasket body and extending to the side away from the shaft center of the shaft hole.

[0016] The annular flange and the annular extension abut in the axial direction to form the anti-disengagement structure.

[0017] The limiting structure is provided between the outer circular wall surface of the annular flange and the hole wall of the central through hole.

[0018] In the optional implementation of the utility model, the gasket body is further provided with a plurality of channels in the circumferential direction on the shaft side end surface away from the annular flange.

[0019] Each channel extends in the radial direction of the shaft hole.

[0020] The rotor assembly is implemented as follows:

[0021] A rotor assembly, comprising: a rotor core, a plurality of magnets arranged on the circumferential outer wall of the rotor core at intervals along the circumferential direction of the rotor core, an axial sleeve sleeved on the outer circumferential side of the plurality of magnets to wrap the plurality of magnets and the rotor core, and a pair of cover plates arranged at the axial two ends of the rotor core respectively; wherein

[0022] The side end of each of the pair of cover plates away from the rotor core is further provided with an axial limiting assembly.

[0023] In the optional implementation of the utility model, the annular fixing sleeve is adapted to be connected with the cover plate by welding.

[0024] In the optional implementation of the utility model, the annular fixing sleeve further comprises an annular connecting part arranged at the axial side end of the annular body away from the annular extension part and extending to the side of the axial center of the central through hole.

[0025] The annular connecting part is used for connecting with the cover plate.

[0026] In the optional implementation of the utility model, the cover plate comprises an inner ring with an axial center hole, an outer ring arranged on the outer side of the inner ring, and an annular accommodating cavity arranged between the inner ring and the outer ring.

[0027] A step is formed between the annular accommodating cavity and the inner ring, and an extension ring in the form of a protrusion is arranged on the inner hole edge of the inner ring corresponding to the axial center hole.

[0028] An annular limiting cavity is formed between the step and the extension ring.

[0029] In the optional implementation of the utility model, a support gasket with one end abutting against the annular gasket is further embedded in the central through hole.

[0030] The support gasket is formed with an axial through hole in communication with the shaft hole, and the inner diameter of the axial through hole is slightly larger than the inner diameter of the shaft hole.

[0031] The electronic water pump of the utility model is realized as follows:

[0032] An electronic water pump, comprising: the rotor assembly.

[0033] The utility model discloses the following beneficial effects are obtained: the shaft limiting assembly can guarantee the position of the rotor assembly in the electronic water pump in the axial direction, guarantee that the rotor assembly does not move in the axial direction in the electronic water pump, make the rotor core and the stator core of the motor align in the axial direction, guarantee that the magnet leakage is minimum, and further guarantee the use performance of the motor structure in the water pump.

[0034] Furthermore, for the annular fixing sleeve and the annular gasket included in the shaft limiting assembly, because the limiting structure in the concave-convex cooperation exists, when the electronic water pump using the shaft limiting assembly works, the impeller on the rotating shaft starts to rotate under the driving of the rotor assembly, and then the annular gasket and the bearing rub. In this process, the relative rotation between the annular gasket and the annular fixing sleeve can be avoided, and the service life of the annular fixing sleeve due to wear and tear can be shortened, that is, the shaft limiting assembly of the utility model can improve the reliability and stability during the long-term use of the electronic water pump. In addition, the annular gasket and the annular fixing sleeve adopt an assembled structure, and the limiting structure and the anti-disengagement structure are used to keep the consistency of the two during the movement, and the assembled structure is more durable and reliable than the injection-molded structure. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 The structure diagram of the shaft limiting assembly of the utility model is applied to a specific rotor assembly.

[0036] Figure 2 The cooperation structure diagram of the annular fixing sleeve, the annular gasket and the supporting gasket of the shaft limiting assembly of the utility model.

[0037] Figure 3 The first perspective structure diagram of the annular fixing sleeve of the shaft limiting assembly of the utility model.

[0038] Figure 4 The second perspective structure diagram of the annular fixing sleeve of the shaft limiting assembly of the utility model.

[0039] Figure 5 The structure diagram of the annular gasket of the shaft limiting assembly of the utility model.

[0040] Figure 6 The structure diagram of the cover plate of the shaft limiting assembly of the utility model.

[0041] In the figure: axial sleeve 1, cover plate 2, inner ring 21, shaft center hole 22, outer ring 23, annular accommodating cavity 24, step 25, extension ring 26, annular fixing sleeve 3, center through hole 31, annular body 32, annular extension 33, annular connecting part 34, connecting wall 35, annular gasket 4, shaft hole 41, gasket body 42, annular flange 43, channel 44, boss 51, groove 52, support gasket 6, axial through hole 61, rotor core 7, rotating shaft 8, magnet 9. DETAILED DESCRIPTION

[0042] In order to make the content of the utility model more easily be clearly understood, the following according to specific embodiment and combining with the drawings, the utility model is further explained in detail.

[0043] Example 1:

[0044] Please refer to Figures 1 to 6 As shown in the figure, the embodiment provides a shaft limiting assembly, which comprises: annular fixing sleeve 3 formed with center through hole 31, and annular gasket 4 formed with shaft hole 41 and adapted to be partially embedded in center through hole 31;Wherein the matching surface of center through hole 31 and annular gasket 4 is spaced apart in circumferential direction and provided with a plurality of limiting structures in concave-convex cooperation. And the annular fixing sleeve 3 and the annular gasket 4 are also provided with anti-disengagement structure adapted to axially abut.

[0045] Next in detail, first about the limiting structure of the embodiment:

[0046] In combination with an example of an optional implementation, the limiting structure adopted by the embodiment includes a plurality of bosses 51 distributed in circumferential direction on the inner wall surface of center through hole 31, and a plurality of grooves 52 provided on the outer circular wall surface of annular gasket 4 and adapted to one-to-one cooperate with a plurality of bosses 51. Of course, theoretically, the bosses 51 and grooves 52 here can also be reversed, that is, the grooves 52 are provided on the inner wall surface of center through hole 31, and the bosses 51 are provided on the outer circular wall surface of annular gasket 4. The embodiment does not make absolute limitation on the specific implementation of the limiting structure here.

[0047] The drawings of the embodiment only take the case that bosses 51 are designed on the inner wall surface of center through hole 31 and grooves 52 are designed on the outer circular wall surface of annular gasket 4. For this, it needs to be explained that, as for the boss 51, the whole is along the axial direction of the center through hole 31, so as to facilitate the assembly of the boss 51 and the groove 52 during the process of inserting the annular gasket 4 into the center through hole 31 along the axial direction. For this, the axial length of the boss 51 can be equal to the axial length of the center through hole 31, or the axial length of the boss 51 can be less than the axial length of the center through hole 31. The embodiment does not make absolute limitation on this.

[0048] Next, it needs to be explained that, as for the anti-disengagement structure:

[0049] The annular fixing sleeve 3 of the embodiment, in combination with an optional case shown in the drawings, comprises an annular body 32 for forming a central through hole 31, and an annular extension 33 arranged at one axial end of the annular body 32 and extending to the side of the axial center of the central through hole 31.

[0050] The annular gasket 4 adopted by the embodiment comprises a gasket body 42 formed with an axial hole 41, and an annular flange 43 connected to one axial end of the gasket body 42 and extending to the side away from the axial center of the axial hole 41. Based on this structure, when the annular gasket 4 and the cover plate 2 are assembled in place, the outer circular wall surface of the annular flange 43 is used to match the hole wall of the central through hole 31; the annular flange 43 is also adapted to abut against the annular extension 33. The limiting structure is arranged between the outer circular wall surface of the annular flange 43 and the hole wall of the central through hole 31, and the annular flange 43 abuts against the annular extension 33 in the axial direction to form the anti-disengagement structure.

[0051] Based on the above, that is, the annular gasket 4 and the annular fixing sleeve 3 form reliable limiting cooperation in both axial and radial directions along the axial hole 41. As for the cooperation of the annular gasket 4 and the annular fixing sleeve 3 in the radial direction, gap cooperation is optionally adopted to improve the smoothness of the mutual assembly process of the annular gasket 4 and the annular fixing sleeve 3. In this regard, in terms of material, the annular fixing sleeve 3 can be made of stainless steel. The annular gasket 4 can be made of ceramic material.

[0052] In summary, for the shaft limiting assembly of the embodiment:

[0053] As for the annular fixing sleeve 3 and the annular gasket 4 included in the shaft limiting assembly, due to the existence of the limiting structure in the concave-convex cooperation, when the electronic water pump using the shaft limiting assembly works, the impeller on the shaft 8 starts to rotate under the driving of the rotor assembly, and then the annular gasket 4 rubs against the bearing sleeved on the shaft 8. In this process, relative rotation between the annular gasket 4 and the annular fixing sleeve 3 can be avoided, and the service life of the annular fixing sleeve 3 due to wear can be shortened, that is, the shaft limiting assembly of the utility model can improve the reliable stability thereof during long-term use of the electronic water pump.

[0054] Embodiment 2:

[0055] Please refer to Figures 1 to 6On the basis of the shaft limiting assembly of Embodiment 1, the present embodiment provides a rotor assembly, which comprises a rotor core 7, a plurality of magnets 9 arranged on the circumferential outer wall of the rotor core 7 at intervals along the circumferential direction of the rotor core 7, an axial sleeve 1 sleeved on the outer circumferential side of the plurality of magnets 9 to wrap the plurality of magnets 9 and the rotor core 7, and a pair of cover plates 2 arranged at the axial two ends of the rotor core 7 respectively; one side end of the pair of cover plates 2 away from the rotor core 7 is further provided with one shaft limiting assembly as in Embodiment 1 respectively. As for the specific structure of the rotor core 7, any mature means in the prior art can be selected, and the present embodiment is not absolutely limited in this regard.

[0056] As for the cover plate 2, it generally comprises an inner ring 21 shaped with a shaft center hole 22, an outer ring 23 arranged on the outer side of the inner ring 21, and an annular accommodating cavity 24 arranged between the inner ring 21 and the outer ring 23. The shaft center hole 22 is suitable for the rotation shaft 8 of the rotor assembly applying the shaft limiting assembly to pass through. The annular accommodating cavity 24 is designed to accommodate dynamic balance mud, so as to ensure that the dynamic balance mud does not fall off during the long-term operation of the water pump corresponding to the rotor assembly applying the shaft limiting assembly. The existence of the dynamic balance mud can reduce the unbalance of the rotor assembly in the specific water pump, thereby reducing the fluctuation of the rotor assembly during the operation of the water pump, reducing the vibration and noise of the water pump, and prolonging the service life of the water pump during long-term use.

[0057] Based on the above, in order to facilitate the cover plate 2 to adapt to the shaft limiting assembly, the annular accommodating cavity 24 of the present embodiment is formed with a step 25 between the inner ring 21, and an extension ring 26 in the form of a protrusion is arranged on the inner hole edge of the inner ring 21 corresponding to the shaft center hole 22; an annular limiting cavity is formed between the step 25 and the extension ring 26, and the shaft limiting assembly is arranged corresponding to the annular limiting cavity, that is, the design of the annular limiting cavity provides a matching space for the sealing sleeve unit.

[0058] In order to better ensure the reliable connection between the annular fixing sleeve 3 and the cover plate 2, the annular fixing sleeve 3 further comprises an annular connecting part 34 arranged on the shaft side end of the annular body 32 away from the annular extension part 33 and extending to the side away from the center of the through hole 31. It should be noted that the annular connecting part 34 is used to be embedded into the annular limiting cavity to be connected with the cover plate 2, so as to realize the primary positioning of the cover plate 2 and the annular fixing sleeve 3 through the cooperation of the annular connecting part 34 and the annular limiting cavity. On this basis, an connecting wall 35 substantially parallel to the axial direction of the center through hole 31 is arranged on the outer circular wall of the annular connecting part 34, which is used for welding connection with the cover plate 2. The connecting wall 35 is mainly used for welding connection with the step 25 on the cover plate 2.

[0059] Based on the above structure, in an optional implementation, a plurality of recessed channels 44 are further arranged in the circumferential direction on the axial side end surface of the gasket body 42 opposite the annular flange 43; each channel 44 extends in the radial direction of the shaft hole 41. Here, the design of the plurality of channels 44 can be used to reduce the friction area formed between the annular gasket 4 and the bearing provided on the shaft 8 (in the prior art, a bearing is generally provided on the shaft 8 on the shaft side end opposite the cover plate 2, and the impeller on the shaft 8 starts to rotate under the drive of the rotor assembly, then the annular gasket 4 rubs against the bearing), reduce friction loss, and thus increase the service life of the bearing (i.e. prolong the service life of the water pump using the shaft limiting assembly of the present embodiment); it can also be used to store medium and increase the lubricity between the bearing, the purpose is also to reduce the friction loss, and thus increase the service life of the bearing (i.e. prolong the service life of the water pump)

[0060] Finally, regarding the shaft limiting assembly of the present embodiment, the following improvements can also be made: the central through hole 31 is further embedded with a support gasket 6 abutting against the annular gasket 4 at one end; the support gasket 6 is formed with an axial through hole 61 communicating with the shaft hole 41, and the inner diameter of the axial through hole 61 is slightly larger than the inner diameter of the shaft hole 41. Based on this structure, when the support gasket 6 and the annular fixing sleeve 3 are assembled in place, the support gasket 6 also abuts against the extension ring 26 of the cover plate 2, so that the entire support gasket 6 is limited between the extension ring 26 and the inner wall of the central through hole 31 of the annular fixing sleeve 3 in the radial direction of the shaft hole 41. Here, the design of the support gasket 6 can form a limit in the axial direction for the annular gasket 4, preventing the annular gasket 4 from moving axially during use. In terms of material, the support gasket 6 can be made of point bakelite or plastic material.

[0061] In summary, for the shaft limiting assembly of the present embodiment, the assembly process is as follows: first, the annular gasket 4 is assembled into the central through hole 31 of the annular fixing sleeve 3, then the support gasket 6 is assembled, and after the three are assembled into a whole sealing piece, the sealing piece is sleeved with the shaft 8 of the rotor assembly of the electronic water pump, and a bearing is assembled between the annular gasket 4 and the shaft 8, and after the cooperation with the shaft 8 is completed, the annular fixing sleeve 3 is welded and fixed with the cover plate 2. For the annular fixing sleeve 3 and the annular gasket 4, due to the presence of the concave-convex limiting structure, when the electronic water pump using the shaft limiting assembly of the present embodiment is working, the impeller on the shaft 8 starts to rotate under the drive of the rotor assembly, then the annular gasket 4 rubs against the bearing. In this process, it can be avoided that the annular gasket 4 and the annular fixing sleeve 3 rotate relatively to shorten the service life of the annular fixing sleeve 3 due to wear, that is, the shaft limiting assembly of the present embodiment can improve the reliability and stability of the overall shaft limiting assembly during long-term use of the electronic water pump.

[0062] For the rotor assembly in this embodiment, the shaft limiting assembly of Embodiment 1 is used. This ensures that the rotor assembly in the electronic water pump using this assembly is fixed in the axial direction, preventing axial movement of the rotor assembly within the pump. This axial alignment of the motor's rotor core 7 and stator core minimizes magnet leakage, thereby ensuring the performance of the motor structure in the water pump. Furthermore, preventing axial movement of the rotor assembly avoids impeller damage caused by collisions between the impeller and the pump casing, and also prevents shaft wear caused by collisions between the shaft 8 and the bottom of the rear bearing housing used to mate with the rotor shaft. This effectively ensures the pump's performance and extends its overall service life.

[0063] Example 3:

[0064] Please see Figures 1 to 6 As shown, based on the rotor assembly of Embodiment 2, this embodiment provides an electronic water pump, including: the rotor assembly of Embodiment 2. For the electronic water pump of this embodiment, the shaft limiting assembly of Embodiment 1 is used. By improving the reliability and stability of the shaft limiting assembly, the overall service life of the electronic water pump can be extended.

[0065] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above are only specific embodiments of this utility model and are not intended to limit this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

[0066] In the description of this utility model, it should be understood that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0067] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0068] In the description of the utility model, it is necessary to explain that the orientation or position relation indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like is the orientation or position relation based on the drawings shown or the orientation or position relation commonly placed when the utility model product is used, and is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element indicated must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second", "third" and the like are only used for distinguishing description, and cannot be understood as indicating or implying relative importance.

[0069] In addition, the terms "horizontal", "vertical", "overhang" and the like do not mean that the components must be absolutely horizontal or overhanging, but can be slightly inclined. For example, "horizontal" only means that its direction is relatively more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0070] In the utility model, unless otherwise explicitly specified and limited, the first feature above or below the second feature can include that the first and second features are in direct contact, or can include that the first and second features are not in direct contact but are in contact through another feature therebetween. Moreover, the first feature above, above and above the second feature includes that the first feature is directly above and obliquely above the second feature, or only means that the horizontal height of the first feature is higher than that of the second feature. The first feature below, below and below the second feature includes that the first feature is directly below and obliquely below the second feature, or only means that the horizontal height of the first feature is less than that of the second feature.

Claims

1. A shaft position limiting assembly, characterized by, The application relates to a shaft limiting assembly. The shaft limiting assembly comprises: a ring-shaped fixing sleeve with a central through hole, and a ring-shaped gasket with a shaft hole and adapted to be partially embedded in the central through hole; wherein the central through hole and the mating surface of the ring-shaped gasket are provided with a plurality of limiting structures in a concave-convex matching mode in a circumferential direction; and 2. The shaft limiting assembly of claim 1, wherein, the ring-shaped fixing sleeve and the ring-shaped gasket are further provided with anti-disengagement structures adapted to axially abut.

3. The shaft limiting assembly of claim 1 or 2, wherein, The limiting structures comprise a plurality of bosses distributed in a circumferential direction on an inner wall surface of the central through hole, and a plurality of grooves provided on an outer circular wall surface of the ring-shaped gasket and adapted to one-to-one match the bosses.

4. The shaft limiting assembly of claim 1 or 2, wherein, The ring-shaped fixing sleeve comprises a ring-shaped body for forming the central through hole, and a ring-shaped extension provided on one shaft side end of the ring-shaped body and extending to one side of the shaft center of the central through hole. The ring-shaped gasket comprises a gasket body with the shaft hole, and a ring-shaped flange connected to one shaft side end of the gasket body and extending to one side of the shaft center away from the shaft hole; the ring-shaped flange and the ring-shaped extension axially abut to form the anti-disengagement structure; 5. The shaft limiting assembly of claim 4, wherein, the limiting structures are arranged between the outer circular wall surface of the ring-shaped flange and the hole wall of the central through hole. The gasket body is further provided with a plurality of channels in an inner recess in a circumferential direction on the shaft side end surface away from the ring-shaped flange; 6. A rotor assembly characterized by, each channel extends in a radial direction of the shaft hole. The application relates to a rotor assembly. The rotor assembly comprises:

7. The rotor assembly of claim 6, wherein a rotor core, a plurality of magnets arranged in a circumferential direction on a circumferential outer wall of the rotor core, an axial sleeve which is sleeved on the outer circumferential side of the plurality of magnets to wrap the plurality of magnets and the rotor core, and a pair of cover plates arranged on the axial two ends of the rotor core; wherein 8. The rotor assembly of claim 6 or 7, wherein, the pair of cover plates are further respectively provided with one shaft limiting assembly as claimed in any one of claims 1 to 5. The ring-shaped fixing sleeve is adapted to be welded to the cover plate.

9. The rotor assembly of claim 6 or 7, wherein, The ring-shaped fixing sleeve further comprises a ring-shaped connecting portion provided on the shaft side end of the ring-shaped body away from the ring-shaped extension and extending to one side of the shaft center away from the central through hole; the ring-shaped connecting portion is used for connecting the cover plate. The cover plate comprises an inner circular ring shaped with a shaft center hole, an outer circular ring provided on the outer side of the inner circular ring, and a ring-shaped accommodating cavity arranged between the inner circular ring and the outer circular ring; 10. The rotor assembly of claim 6 or 7, wherein, a step is formed between the ring-shaped accommodating cavity and the inner circular ring, and a protruding extension ring is arranged on the inner hole edge of the inner circular ring corresponding to the shaft center hole; a ring-shaped limiting cavity is formed between the step and the extension ring.

11. An electronic water pump characterized by comprising: A support gasket is further embedded in the central through hole and abuts against the ring-shaped gasket on one end; the support gasket is formed with an axial through hole communicated with the shaft hole, and the inner diameter of the axial through hole is slightly larger than the inner diameter of the shaft hole. The application relates to a rotor assembly. The rotor assembly comprises: the rotor assembly as claimed in any one of claims 6 to 10.

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