Rotor assembly and motor

Abstract

The invention discloses a rotor assembly and a motor, and relates to the technical field of motors, the rotor assembly comprises an inner iron core, an outer iron core, a plurality of first filling members arranged between the inner iron core and the outer iron core, and a plurality of magnetic steels arranged on the outer side of the outer iron core, the plurality of first filling members are arranged between the outer iron core and the inner iron core, and the plurality of magnetic steels are arranged on the outer side of the outer iron core. The multiple first filling pieces are connected with the inner iron core and the outer iron core, and the multiple first filling pieces are arranged in the circumferential direction of the outer wall of the inner iron core at intervals. The technical scheme provided by the invention aims to solve the problem that the inner iron core and the outer iron core which are wrapped by plastic are easy to crack at the position of the injection welding surface under environmental tests such as cold and hot shock.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a rotor assembly and a motor. Background Technology

[0002] Currently, the rotor assembly of the motor uses an inner iron core and an outer iron core, which are connected by injection molding of plastic material. During environmental testing, such as thermal shock testing, the plastic coating structure of the rotor assembly is prone to breakage, causing the motor to produce noise or the rotor to jam. Increasing the amount of injection molding material will increase the cost of the motor. Figure 1 This is a schematic diagram of the structure of the filler component formed by continuous injection molding between the inner and outer iron cores. Figure 1 The dotted line indicated by the double arrows is the weld line (the weld line is formed by the flow and convergence of filler, and the convergence surfaces often do not fully fuse due to temperature differences). Under environmental tests such as thermal shock tests, the weld line is prone to cracking. Summary of the Invention

[0003] The main objective of this invention is to propose a rotor assembly and motor that aims to solve the problem that plastic-encased inner and outer iron cores are prone to cracking at the injection molding weld joint under environmental tests such as thermal shock.

[0004] To achieve the above objectives, the present invention provides a rotor assembly comprising:

[0005] Inner iron core;

[0006] Outer iron core; the outer iron core is fitted with the inner iron core;

[0007] A plurality of magnets are arranged circumferentially on the outside of the outer iron core; and

[0008] Multiple first fillers are disposed between the outer iron core and the inner iron core, the multiple first fillers connect the inner iron core and the outer iron core, and the multiple first fillers are arranged at intervals along the outer wall of the inner iron core.

[0009] In one embodiment, the plurality of first fillers define a plurality of circumferentially spaced slots between the inner core and the outer core.

[0010] In one embodiment, the plurality of the partitions are evenly spaced apart.

[0011] In one embodiment, the inner wall of the outer core is provided with a plurality of inner protrusions at circumferential intervals, and the outer wall of the inner core is provided with a corresponding number of outer concave portions corresponding to the inner protrusions. The inner protrusions and outer concave portions are opposite to each other. The first filler covers the inner protrusions and fills the gap between the inner protrusions and the outer concave portions.

[0012] In one embodiment, the inner convex portion is recessed inward on both opposite sides in the circumferential direction to form two limiting grooves, and the two ends of the first filler are respectively placed in the two limiting grooves.

[0013] In one embodiment, the sidewall of the limiting groove is curved.

[0014] In one embodiment, the cross-sectional shape of the first filler perpendicular to the axial direction is C-shaped.

[0015] In one embodiment, both the inner convex portion and the outer concave portion extend axially to both ends of the inner core and the outer core.

[0016] In one embodiment, the inner protrusion has an injection port.

[0017] In one embodiment, the rotor assembly further includes a second filler, through which the plurality of magnets are disposed on the outside of the outer core.

[0018] In one embodiment, the second filling member includes a plurality of limiting portions that surround the upper end and lower end of the outer iron core and protrude from the outer surface of the outer iron core and connect the upper end and the lower end. The plurality of limiting portions are distributed circumferentially and form a plurality of receiving cavities. A magnet is disposed in one of the receiving cavities.

[0019] In one embodiment, the upper end and / or the lower end are provided with a plurality of positioning holes for the insertion of positioning pins for positioning the magnet, and a set of positioning holes is connected to a receiving cavity.

[0020] In one embodiment, the first filler and the second filler are integrally formed.

[0021] In one embodiment, the first filler extends axially and has a groove formed on the side near the inner core, the inner core being disposed within the groove.

[0022] In one embodiment, the first filler covers the outer iron core.

[0023] The present invention also proposes an electric motor comprising the rotor assembly described above.

[0024] The technical solution of this invention firstly adopts a separate design by arranging multiple first filler elements at intervals between the inner core and the outer core, thus eliminating the weld surface between the integral injection molded parts that enclose the inner core in related technologies, thereby solving the problem of easy breakage at the weld surface during thermal shock tests; secondly, the method of arranging multiple first filler elements at intervals reduces the amount of filler material used, further reducing costs; thus, it ensures the bonding strength of the inner / outer cores and achieves the goal of low cost and high reliability. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the weld surface of a rotor injection molded part in a related technology;

[0027] Figure 2 This is a schematic diagram of the structure of an embodiment of the rotor mobile phone provided by the present invention;

[0028] Figure 3 for Figure 2 A schematic diagram of the structure for removing the thickness of the filler in the middle;

[0029] Figure 4 for Figure 2 A schematic diagram of a cross-sectional structure perpendicular to the central axis;

[0030] Figure 5 for Figure 2 A schematic diagram of a cross-sectional structure perpendicular to the radial direction.

[0031] Explanation of icon numbers:

[0032] 100, Rotor assembly; 110, Spacing; 120, Arc-shaped surface; 200, Inner iron core; 210, Outer concave portion; 300, Outer iron core; 310, Inner convex portion; 311, Limiting groove; 312, Arc-shaped bend; 320, Positioning boss; 330, Glue injection port; 400, Magnet; 500, First filler; 510, Insertion groove; 600, Second filler; 610, Upper end; 620, Lower end; 630, Limiting portion; 640, Receiving cavity.

[0033] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0035] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0036] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0037] Currently, the rotor assembly of the motor uses an inner iron core and an outer iron core, which are connected by injection molding of plastic material. During environmental testing, such as thermal shock testing, the plastic coating structure of the rotor assembly is prone to breakage, causing the motor to produce noise or the rotor to jam. Increasing the amount of injection molding material will increase the cost of the motor.

[0038] Figure 1 This is a schematic diagram of the structure of the filler formed by continuous injection molding between the inner and outer iron cores. The dotted line indicated by the double arrows in the diagram is the welded surface (the welded surface is formed by the flow and convergence of plastic, and the surface temperature of the converged surfaces is different, so they are often not completely fused). Under environmental tests such as thermal shock tests, the welded surface is prone to cracking, which can cause the magnet to fall off.

[0039] Therefore, the present invention provides a rotor assembly that aims to solve the problem that plastic-encased inner and outer iron cores are prone to cracking at the injection molding weld surface under environmental tests such as thermal shock.

[0040] Please see Figures 2 to 4In one embodiment of the present invention, the rotor assembly 100 includes an inner core 200, an outer core 300 sleeved on the inner core 200, a plurality of first filler members 500 disposed between the inner core 200 and the outer core 300, and a plurality of magnets 400 disposed circumferentially on the outside of the outer core 300. The plurality of magnets 400 can be integrally encapsulated on the outside of the outer core 300 by injection molding; or they can be fixed to the outside of the outer core 300 by adhesive bonding. In one embodiment, there are two first filler members 500, which are symmetrically arranged between the inner core 200 and the outer core 300; in another embodiment, there are three first filler members 500, which are arranged between the inner core 200 and the outer core 300; in other embodiments, the number of first filler members 500 can be five, six, or even more; for better cost-effectiveness, i.e., lower cost and relatively better performance, in this embodiment, there are four first filler members 500. The filling elements 500 are evenly spaced along the circumference. The inner iron core 200 and the outer iron core 300 of the rotor assembly 100 are separated by an intermittent injection molding process, forming a discontinuous injection molding layer. This design makes the injection molding layer discontinuously distributed between the inner iron core 200 and the outer iron core 300, rather than completely covering or forming a continuous whole. That is, the multiple first filling elements 500 are spaced between the inner iron core 200 and the outer iron core 300, and it is not limited whether the first filling elements 500 are connected at the upper or lower end face of the inner iron core 200 and the outer iron core 300.

[0041] It should be noted that the discontinuous injection layer does not mean that the first filler 500 is discontinuous, but rather that it is connected by multiple independent injection areas. Each first filler 500 is an independent injection area, and there are gaps or un-injected parts between these injection areas.

[0042] The technical solution of this invention firstly adopts a separate design by arranging multiple first filler elements 500 at intervals between the inner iron core 200 and the outer iron core 300, thus eliminating the weld surface between the integral injection molded parts that enclose the inner iron core 200 in related technologies, thereby solving the problem of easy breakage at the weld surface in thermal shock tests; secondly, the arrangement of multiple first filler elements 500 at intervals reduces the amount of filler material used, further reducing costs; thus, it ensures the bonding force between the inner and outer iron cores 300 and achieves the goal of low cost and high reliability.

[0043] Please see Figures 2 to 4Taking a scheme with four first filler elements 500 as an example, the filler material is not limited, and plastic materials are usually used; if the motor needs to have buffering and vibration damping capabilities, rubber can be used as the filler. The first filler element 500 can be injection molded individually or as a single piece; that is, in some schemes, the materials of multiple first filler elements 500 can be different. On the one hand, this can improve design flexibility, by using multiple materials in the same product, each material can be injection molded in a specific area according to its characteristics; on the other hand, it can improve product performance by adding an additional material layer in the key areas of the product to improve its strength, heat resistance, or other physical properties.

[0044] In one embodiment, four first filler members 500 define a plurality of slots 110 circumferentially between the inner core 200 and the outer core 300. The plurality of slots 110 are evenly spaced, and a continuous annular gap is defined between the inner core 200 and the outer core 300. The plurality of first filler members 500 disposed within the annular gap separate the annular gap to form a plurality of slots 110. The plurality of slots 110 are evenly distributed, that is, the annular gap is divided into four equal parts, and the lengths of adjacent slots 110 are equal. This ensures the bonding force constituting the rotor assembly 100.

[0045] In other embodiments, two adjacent first filler elements 500 are arranged at intervals, but there is no gap between two adjacent first filler elements 500. For example, the inner core 200 may partially separate two adjacent first filler elements 500, or the outer core 300 may partially separate two adjacent first filler elements 500.

[0046] Reference Figure 4 During the rotation of the rotor assembly 100, the inner iron core 200 and the outer iron core 300 transmit force through the first filler 500. For stable connection, the ratio of the circumferential length of the first filler 500 to the circumferential length of the partition groove 110 is greater than or equal to 1 / 2 and less than or equal to 1. In this embodiment, the ratio of the circumferential length of the first filler 500 to the circumferential length of the partition groove 110 is approximately 2 / 3. This ensures both the connection force between the inner and outer iron cores 300 and achieves the goal of low cost and high reliability.

[0047] To ensure more efficient force transmission and extend the service life of the rotor assembly 100 composed of the inner core 200 and the outer core 300, the inner wall of the outer core 300 is provided with multiple circumferentially spaced inner protrusions 310, and the outer wall of the inner core 200 is provided with a corresponding number of outer concave portions 210 corresponding to the inner protrusions 310. The inner protrusions 310 and the outer concave portions 210 correspond to each other. The first filler 500 covers the inner protrusions 310 and fills the gap between the inner protrusions 310 and the outer concave portions 210. The inner core 200 has a shaft hole in the middle. During rotation, the inner core 200 is driven to rotate, and the side wall of the outer concave portion 210 presses against the first filler 500. The first filler 500 then presses against the outer wall of the inner protrusion 310, thereby driving the outer core 300 to rotate. Compared with pulling the outer core 300 by the first filler 500, the force transmission effect is better, and the efficiency of the rotor assembly 100 is higher.

[0048] To facilitate placement into the mold during injection molding and ensure the processing, the inner wall of the outer iron core is also provided with a positioning boss 320, which extends axially. In one embodiment, the positioning boss 320 is disposed in one of the slots; in other embodiments, the positioning boss 320 is disposed in two opposite slots.

[0049] Four first filler elements 500 define multiple slots 110 circumferentially between the inner iron core 200 and the outer iron core 300. The evenly distributed slots 110 ensure that the inner iron core 200 and the outer iron core 300 are subjected to uniform force in the circumferential direction. The cross-sectional shape of the slots 110 in the axial direction is fan-shaped, which is equivalent to the shape of the fan surface after the fan is unfolded. The top and bottom are arc-shaped and the sides are straight, which not only ensures the bonding force of the inner / outer iron core 300, but also achieves the purpose of low cost and high reliability.

[0050] To ensure a more secure connection between the first filler 500 and the inner protrusion 310, the inner protrusion 310 is recessed inward on both sides in the circumferential direction, forming two limiting grooves 311 respectively. The two ends of the first filler 500 are respectively placed in the two limiting grooves 311. The cross-sectional shape of the first filler 500 in the axial direction is C-shaped, and the two ends of the C-shape are embedded in the limiting grooves 311. The inner protrusion 310 of the inner core 200 and the C-shaped design of the first filler 500 fit together to prevent relative slippage or separation when subjected to external forces, thereby enhancing structural stability.

[0051] In other embodiments, the cross-sectional shape of the first filler 500 in the axial direction is U-shaped, and the first filler 500 fits into the inner protrusion 310 to enhance structural stability.

[0052] To improve the bonding force between the inner core 200 and the first filler 500, in one embodiment, the first filler 500 extends axially and forms a groove 510 on the side near the inner core 200. The inner core 200 is disposed in the groove 510. In this embodiment, the upper and lower ends of the first filler 500 extend radially to both ends of the inner core 200, engaging the inner core 200 to form an interlocking structure, thereby improving the bonding strength.

[0053] Furthermore, the first filler 500 covers the outer iron core 300, that is, the outer iron core 300 passes through the middle of the first filler 500.

[0054] Furthermore, the sidewall of the limiting groove 311 is curved 312, and the sidewall is a continuous curve that constitutes the limiting groove 311. Setting the sidewall of the groove to be curved 312 is more conducive to dispersing the force applied to the first filler 500, avoiding stress concentration, and avoiding cracking of the first filler 500.

[0055] Similarly, the outer surfaces of the inner convex portion 310 and the outer concave portion 210 are arc-shaped curved surfaces 120 in the axial cross-section.

[0056] As described above, the inner core 200 and the outer core 300 are connected by the first filler 500 and the force is transmitted through the first filler 500. In one embodiment, the inner convex portion 310 and the outer concave portion 210 both extend axially to the two ends of the inner core 200 and the outer core 300, that is, the inner convex portion 310 is columnar, dispersing the force in the axial direction and avoiding stress concentration.

[0057] In other embodiments, the inner protrusion 310 is a portion extending axially along one or both ends to the inner core 200. In one embodiment, the inner protrusion 310 has an injection port; a first filler 500 covers the inner protrusion 310; in other embodiments, the injection port may be located on a mold.

[0058] Reference Figure 2 and Figure 4 In one embodiment, the rotor assembly 100 further includes a second filler 600, through which a plurality of magnets 400 are disposed on the outside of the outer iron core 300, and the second filler 600 covers the plurality of magnets 400; ensuring the stability of the connection of the magnets 400; the second filler 600 and the first filler 500 are separately injection molded and do not affect each other.

[0059] In one embodiment, the second filler 600 includes a plurality of limiting portions 630 that surround the upper end portion 610 and the lower end portion 620 of the outer iron core 300 and protrude from the outer surface of the outer iron core 300 and connect the upper end portion 610 and the lower end portion 620. The plurality of limiting portions 630 are distributed circumferentially and form a plurality of receiving cavities 640. A magnet 400 is disposed in a receiving cavity 640.

[0060] The second filler 600 forms a frame structure, covering the magnet 400, the inner iron core 200, and the outer iron core 300. The first filler 500 is disposed between the inner iron core 200 and the outer iron core 300. The first filler 500 and the second filler 600 are formed by secondary injection molding.

[0061] In one embodiment, the first filler 500 and the second filler 600 are integrally formed. The upper end 610 and / or the lower end 620 are provided with multiple sets of positioning holes for the positioning pins of the positioning magnet 400 to be inserted. One set of positioning holes is connected to a receiving cavity 640. During the injection molding process, the mold fixes the magnet 400 by positioning pins. The outer iron core 300 and the inner iron core 200 are sleeved. The solid part is inserted into the partition groove 110, defining the cavity of the first filler 500 and the second filler 600. Glue is injected through the injection port 330. The first filler 500 is connected to the upper end 610 and the lower end 620 to form an integral structure.

[0062] The present invention also proposes an electric motor, which includes a rotor assembly 100 and a stator assembly that cooperates with the rotor assembly 100. The specific structure of the rotor assembly 100 is as described in the above embodiments. Since the present motor adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0063] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A rotor assembly, characterized in that, include: Inner iron core; Outer iron core; the outer iron core is fitted with the inner iron core; Multiple magnets are arranged circumferentially on the outside of the outer iron core; and Multiple first fillers are disposed between the outer iron core and the inner iron core, the multiple first fillers connect the inner iron core and the outer iron core, and the multiple first fillers are arranged at intervals along the outer wall of the inner iron core.

2. The rotor assembly as claimed in claim 1, characterized in that, The plurality of first fillers define a plurality of circumferentially spaced slots between the inner core and the outer core.

3. The rotor assembly as claimed in claim 2, characterized in that, The multiple slots are evenly spaced.

4. The rotor assembly as claimed in claim 2, characterized in that, The inner wall of the outer core is provided with a plurality of inner protrusions at intervals along the circumference, and the outer wall of the inner core is provided with a corresponding number of outer concave portions corresponding to the inner protrusions. The inner protrusions and outer concave portions are opposite to each other. The first filler covers the inner protrusions and fills the gap between the inner protrusions and the outer concave portions.

5. The rotor assembly as claimed in claim 4, characterized in that, The inner convex portion is recessed inward on both sides in the circumferential direction to form two limiting grooves, and the two ends of the first filler are respectively placed in the two limiting grooves.

6. The rotor assembly as claimed in claim 5, characterized in that, The sidewall of the limiting groove is curved.

7. The rotor assembly as claimed in claim 5, characterized in that, The outer surfaces of the inner convex portion and the outer concave portion are arc-shaped curved surfaces in the axial cross-section.

8. The rotor assembly as claimed in claim 5, characterized in that, The cross-sectional shape of the first filler perpendicular to the axial direction is C-shaped.

9. The rotor assembly as claimed in claim 4, characterized in that, Both the inner convex portion and the outer concave portion extend axially to both ends of the inner iron core and the outer iron core.

10. The rotor assembly as claimed in claim 9, characterized in that, The inner protrusion is provided with an injection port.

11. The rotor assembly as claimed in any one of claims 1 to 10, characterized in that, The rotor assembly also includes a second filler, through which the plurality of magnets are disposed on the outside of the outer core.

12. The rotor assembly as claimed in claim 11, characterized in that, The second filling member includes multiple limiting parts that surround the upper and lower ends of the outer iron core and protrude from the outer surface of the outer iron core and connect the upper and lower ends. The multiple limiting parts are distributed circumferentially and form multiple receiving cavities. A magnet is disposed in one of the receiving cavities.

13. The rotor assembly as claimed in claim 12, characterized in that, The upper end and / or the lower end are provided with a plurality of positioning holes for the insertion of positioning pins for positioning the magnet, and a set of positioning holes is connected to a receiving cavity.

14. The rotor assembly as claimed in claim 11, characterized in that, The first filler and the second filler are integrally formed; and / or, the first filler extends axially and has a groove formed on the side near the inner iron core, the inner iron core being disposed in the groove; and / or, the first filler covers the outer iron core.

15. An electric motor, characterized in that, Includes the rotor assembly as described in any one of claims 1 to 14.

Images