Motor stator and external rotor motor comprising same

Abstract

The utility model discloses a motor stator and an external rotor motor comprising the same, the motor stator comprises a stator iron core, the stator iron core comprises a plurality of first iron core punching sheets and a plurality of second iron core punching sheets, each of the first iron core punching sheets and the second iron core punching sheets comprises an annular yoke part and a plurality of stator teeth extending outwards from the radial direction of the annular yoke part, the second iron core punching sheet further comprises a supporting part located on the radial inner side of the annular yoke part, and the supporting part is connected with a motor shaft of the outer rotor motor in a matched mode. The plurality of second iron core punching sheets are sequentially stacked in the axial direction, and the plurality of first iron core punching sheets are sequentially stacked at the two ends of the plurality of second iron core punching sheets in the axial direction respectively, so that sinking structures with concave middle parts are formed at the two ends of the stator iron core. The motor stator structure provided by the utility model is simple in composition, does not need to be fixed through a complex process, greatly reduces the cost and weight of a product under the condition that the performance of the stator assembly is ensured, can optimize the assembly space of parts, and reduces the thickness of the whole machine.

Description

TECHNICAL FIELD

[0001] The utility model relates to motor design technical field especially relates to a kind of motor stator and the outer rotor motor comprising it, mainly for commercial robot field. BACKGROUND

[0002] In the existing robot wheel hub motor stator structure, the core assembly is mainly riveted by a plurality of punching sheets, and the structure of the core assembly mainly has two kinds, the first kind is the annular structure composed of yoke and tooth, and the second kind is formed by the punching sheet with support structure on the inner side of yoke, wherein the first kind of core assembly needs to cooperate with plastic support, for forming the shaft hole of the motor shaft, such as the stator in patent No. CN108964298A is composed of core, support and sleeve, more parts, complex installation process.

[0003] And although the second kind of core assembly has simple structure composition, the thickness of the core is consistent from inside to outside, and the whole is relatively thick and heavy, which leads to large motor mass. And due to the single structure of the punching sheet constituting the core assembly, in order to control the thickness of the motor, the overall thickness of the core assembly can only be reduced, but this will cause the performance of the motor to be reduced, on the contrary, in order to achieve the required performance, the core stack thickness must be increased by increasing the axial space inside the motor, in addition, the motor as a whole also needs to install bearing, so the overall thickness of such wheel hub motor is also large, which cannot meet the lightweight requirement of the existing robot wheel hub motor.

[0004] In summary, how to design a robot wheel hub motor with simple structure composition and installation process, which can meet the performance requirements and realize lightweight design, is a technical problem to be solved at present. INVENTION CONTENTS

[0005] In order to solve the technical problems of complex installation process, large overall thickness and mass of the wheel hub motor stator structure in the prior art, the utility model provides a motor stator and an outer rotor motor comprising the same to solve the above problems.

[0006] The utility model provides a kind of motor stator, including stator core, the stator core includes a plurality of first core punching sheet and a plurality of second core punching sheet, the first core punching sheet and second core punching sheet all include annular yoke and a plurality of stator teeth extending radially outward from the annular yoke, wherein the second core punching sheet further includes support portion located on the radial inner side of annular yoke, and the support portion is connected with the motor shaft of outer rotor motor.

[0007] A plurality of second core punching sheets are sequentially stacked along the axial direction, and a plurality of first core punching sheets are sequentially stacked along the axial direction at both ends of the plurality of second core punching sheets, so that the both ends of the stator core form a sunken structure with a concave middle part.

[0008] In the optional embodiment of the utility model, riveting is used to fix the core punching sheets which are stacked in sequence.

[0009] In the optional embodiment of the utility model, the first core punching sheet and the second core punching sheet are provided with the riveting points which protrude to the same side on the corresponding stator teeth, and the surfaces of the stator teeth on the other side of the riveting points form the riveting blind holes.

[0010] In the optional embodiment of the utility model, the stator teeth provided with the riveting points are arranged at intervals with the stator teeth not provided with the riveting points.

[0011] In the optional embodiment of the utility model, one end of the stator core provided with the riveting points is further provided with a third core punching sheet, the third core punching sheet comprises an annular yoke part and a plurality of stator teeth extending radially outward from the annular yoke part, and the stator teeth of the third core punching sheet are provided with the riveting through holes corresponding to the riveting points.

[0012] In the optional embodiment of the utility model, the axial depth of the sinking structure is 5mm-10mm.

[0013] In the optional embodiment of the utility model, the radial distance from the center of the motor shaft to the inner circumferential surface of the annular yoke part of the first core punching sheet and the second core punching sheet is equal.

[0014] In the optional embodiment of the utility model, the radial gap is formed between the support part and the annular yoke part of the second core punching sheet, and the radial gap forms the wire storage groove for accommodating the coupling wire.

[0015] In the optional embodiment of the utility model, a plurality of wire storage grooves are arranged at intervals in the circumferential direction.

[0016] In the optional embodiment of the utility model, the number of the wire storage grooves is 3-6.

[0017] In the optional embodiment of the utility model, the center of the support part is provided with a shaft hole matched with the motor shaft, and the inner circumferential surface of the shaft hole is provided with a key groove matched with the flat key on the surface of the motor shaft.

[0018] The utility model further provides an external rotor motor which comprises a rotor, a motor shaft and the motor stator.

[0019] In the optional embodiment of the utility model, the inner diameter of the sinking structure is greater than the outer diameter of the bearing, and the bearing at the input end of the motor shaft is partially sunk into the sinking structure.

[0020] The utility model has the advantages of:

[0021] (1) The motor stator is formed by laminating two kinds of core punching sheets, has simple structure, does not need to be fixed through complex process, can form a sunken structure with a concave bottom at both ends of the stator core while forming a support part at the same time, greatly reduces the cost and weight of the product under the condition of ensuring the performance of the stator assembly, optimizes the part assembly space, and reduces the thickness of the whole machine.

[0022] (2) The utility model discloses a storage wire groove for accommodating the connecting wire is left between the support part and the annular yoke part of the second core punching sheet, the hollow storage wire groove greatly reduces the weight of the core assembly, makes the whole machine more light, and the storage wire groove can place the wire end of the core wire, so that the internal space of the hub motor is more compact. BRIEF DESCRIPTION OF DRAWINGS

[0023] The utility model is further illustrated below in combination with the drawings and embodiments.

[0024] Figure 1 It is the plan view of the stator core in the motor stator of the utility model;

[0025] Figure 2 It is the distribution schematic view of three kinds of core punching sheets in the stator core of the utility model;

[0026] Figure 3 It is the riveting point schematic view of the surface of the core punching sheet in the utility model;

[0027] Figure 4 It is the perspective view of the stator core in the utility model;

[0028] Figure 5 It is the axial sectional view of the specific implementation of the external rotor motor in the utility model.

[0029] In the drawing, 1, stator core, 101, first core punching sheet, 102, second core punching sheet, 103, third core punching sheet, 2, annular yoke part, 3, stator tooth, 4, support part, 5, shaft hole, 501, key groove, 6, riveting point, 7, riveting blind hole, 8, riveting through hole, 9, sunken structure, 10, storage wire groove, 11, connecting wire, 12, rotor, 13, motor shaft, 14, bearing. DETAILED DESCRIPTION

[0030] The embodiments of the utility model are described in detail below, the examples of the embodiments are shown in the drawings, wherein the same or similar signs represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary, only for explaining the utility model, and cannot be understood as limiting the utility model.

[0031] The utility model discloses motor stator includes stator core 1 and the enameled wire of winding on stator core 1, the utility model mainly improves the structure of stator core 1, and the following specific embodiment is described.

[0032] Embodiment one

[0033] As Figures 1-4 Stator core 1 includes a plurality of first core punching sheet 101 and a plurality of second core punching sheet 102, and the first core punching sheet 101 and the second core punching sheet 102 both include an annular yoke 2 and a plurality of stator teeth 3 extending radially outward from the annular yoke 2, wherein the second core punching sheet 102 further includes a support portion 4 located radially inward of the annular yoke 2, and the support portion 4 is connected with the motor shaft 13 of the outer rotor 12 motor.

[0034] A plurality of second core punching sheets 102 are sequentially stacked along the axial direction, and a plurality of first core punching sheets 101 are sequentially stacked along the axial direction at both ends of the plurality of second core punching sheets 102, so that both ends of the stator core 1 form a sunken structure 9 with a concave middle portion.

[0035] The support portion 4 is integrally formed with the annular yoke 2 and the stator teeth 3 in the second core punching sheet 102, compared with the prior art that the stator assembly is formed by assembling the core, the support and the shaft sleeve, the utility model discloses omit the support and the shaft sleeve, only need a kind of component of stator core 1, structure composition is simple, and installation is also more convenient.

[0036] The annular yoke 2 and the stator teeth 3 in the first core punching sheet 101 and the second core punching sheet 102 are sequentially and oppositely arranged, the utility model discloses that the sunken structure 9 is formed inside the annular yoke 2 of the stator core 1, since the main component of the stator core 1 generating closed magnetic circuit is the annular yoke 2 and the stator teeth 3, therefore the thickness change of the radial inner portion of the annular yoke 2 has very small influence on electromagnetic performance, the utility model discloses that the support portion 4 is additionally arranged inside the annular yoke 2 of the second core punching sheet 102, without changing the thickness of the overall annular yoke 2 of the stator core 1, by the design of the sunken structure 9 portion, the installation space position of other parts (such as bearing 14) is increased, so as to reduce the overall size of the machine. In this way, not only the material cost is reduced, but also the manual manufacturing cost is effectively reduced. Thus, the performance requirements can be met under the condition of subtractive material.

[0037] As Figure 1As shown, the center of the support part 4 has a shaft hole 5, which can be used to assemble the motor shaft 13. In order to improve the stability of the motor shaft 13 assembly, the inner circumferential surface of the shaft hole 5 has a key groove 501 matched with the flat key surface of the motor shaft 13. In the process of motor assembly, the shaft hole 5 needs to be pressed with the motor shaft 13, and in the process of pressing, the key groove 501 will be aligned with the flat key on the outer circumference of the motor shaft 13 for pressing. The design of the key groove 501 can make the pressing of the motor shaft 13 and the stator core 1 more stable, and ensure that the stator core 1 will not be loose and even fall off when the motor rotates.

[0038] The greater the axial depth of the sinking structure 9, the more conducive to the lightweight and small design of the motor. However, if the axial depth of the sinking structure 9 is too large, the length of the support part 4 will be reduced, the matching size of the support part 4 and the motor shaft 13 will be reduced, and the assembly stability of the motor shaft 13 will be reduced. In the commonly used robot hub motor, the thickness of the stator assembly is usually about 30mm. It has been verified that the axial depth of the sinking structure 9 in the embodiment is preferably 5mm-10mm.

[0039] For the connection mode of adjacent core punching sheets, welding, buckle connection or riveting can be used.

[0040] The embodiment adopts the commonly used riveting process, and the adjacent core punching sheets are fixed by riveting. The specific structure of each core punching sheet is as follows:

[0041] The first core punching sheet 101 includes an annular yoke part 2 and a plurality of stator teeth 3 extending radially outward from the annular yoke part 2, and the stator teeth 3 have a riveting point 6 protruding to the same side. The surface of the stator teeth 3 on the other side of the riveting point 6 forms a riveting blind hole 7. The riveting point 6 can be arranged on part of the stator teeth 3, or on each stator tooth 3. In the embodiment, the stator teeth 3 provided with the riveting point 6 are arranged at intervals with the stator teeth 3 not provided with the riveting point 6.

[0042] The second core punching sheet 102 includes an annular yoke part 2 and a plurality of stator teeth 3 extending radially outward from the annular yoke part 2, which is the same as the first core punching sheet 101. The stator teeth 3 on the second core punching sheet 102 are also provided with the riveting point 6 and the riveting blind hole 7. Different from the first core punching sheet 101, the radial inner side of the annular yoke part 2 of the second core punching sheet 102 is connected with the support part 4, and the center of the support part 4 has a shaft hole 5 matched with the motor shaft 13.

[0043] Among the two adjacent core punching sheets, the riveting point 6 on one core punching sheet is opposite the riveting blind hole 7 of the other core punching sheet, and during assembly, the riveting point 6 is aligned with the riveting blind hole 7 for riveting and fixing.

[0044] In order to ensure that the electromagnetic performance reaches the optimal state, the radial distance from the center of the motor shaft 13 to the inner circumferential surface of the annular yoke part 2 of the first and second core punching sheets 101 and 102 is preferably equal.

[0045] Embodiment Two

[0046] In Embodiment One, each core punching sheet has a riveting point 6 protruding to one side, so that after the assembly of the stator core 1 is completed, there are several protruding riveting points 6 at one end of the stator core 1, and these protruding structures will squeeze the remaining components during the assembly of the motor and affect the positioning balance of the remaining components. Therefore, this embodiment is provided with a third core punching sheet 103 at the end of the stator core 1 where the protruding riveting point 6 is located, the third core punching sheet 103 includes an annular yoke part 2 and a plurality of stator teeth 3 extending radially outward from the annular yoke part 2, and the stator teeth 3 of the third core punching sheet 103 have riveting through holes 8 corresponding to the riveting points 6. The third core punching sheet 103 only needs to be provided with one piece, and the riveting point 6 on the first core punching sheet 101 at the end is riveted into the riveting through hole 8, so that the end of the assembled stator core 1 is more flat without protrusions, which is convenient for the positioning and assembly of other components.

[0047] Embodiment Three

[0048] On the basis of the above embodiments, the support part 4 of the second core punching sheet 102 has a radial gap with the annular yoke part 2, and the radial gap forms a wire storage groove 10 (as shown in Figure 1 and Figure 5 ) for accommodating the coupling wire 11. For a hub motor, the internal space is very compact, and the lead-out wire of the stator often occupies a large internal space. The design of the wire storage groove 10 can solve this situation, as shown in Figure 5 , after the coupling wire 11 of the motor is welded, the excess wire end can be placed in the wire storage groove 10, and it will not occupy the excess internal space of the motor, so that the whole machine can be made thinner. In addition, the design of the wire storage groove 10 forms a hollow structure between the support part 4 and the annular yoke part 2, which greatly reduces the weight of the core assembly, so that the whole machine is more lightweight. Nowadays, the cost of materials is increasing, and this design can greatly reduce the cost of the whole machine.

[0049] The number of wire storage grooves 10 is preferably 3-6. In this embodiment, the wire storage groove 10 is arc-shaped, and three wire storage grooves 10 are uniformly distributed in the circumferential direction for accommodating the three wire ends of a three-phase motor.

[0050] Embodiment Four

[0051] An outer rotor motor includes a rotor 12, a motor shaft 13, and a motor stator as described above, the rotor 12 is located outside the motor stator, and the motor shaft 13 is further provided with a bearing 14 at both ends.

[0052] The inner diameter of the sunken structure 9 is larger than the outer diameter of the bearing 14, and in this embodiment, the bearing 14 at the input end of the motor shaft 13 is partially sunken into the sunken structure 9. Figure 5 As shown in the figure, the output end of the motor shaft 13 is located at the upper side, and the bearing 14 at the lower side is located at the input end of the motor shaft 13, close to the rear end cover of the motor, and is partially arranged in the sunken structure 9 at the lower half, which can save the axial dimension of the motor, and the bearing 14 at the upper side is generally not extended into the sunken structure 9 at the upper half, because the connecting line 11 needs to be extended into the sunken structure 9 at the upper half, and if the bearing 14 is further extended, it may interfere with the connecting line 11, causing the connecting line 11 to be rubbed and broken.

[0053] The sunken structure 9 and the slot design do not reduce the stacking thickness of the stator core 1, but optimize the shape under the condition that the stacking thickness and the outer diameter are unchanged, so that the performance standard can be guaranteed and the cost can be reduced.

[0054] In the description of the present application, it should be understood that the terms "upper", "lower", "inner", "outer", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0055] In addition, the terms "first", "second" and the like are only for the purpose of description, and cannot be understood as indicating or implying relative importance. In the description of the present application, it should be noted that, unless otherwise specified and limited, the meaning of "several" is two or more.

[0056] In the present specification, the illustrative description of the terms does not necessarily refer to the same embodiment. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments in a suitable manner.

[0057] Based on the above ideal embodiments according to the present application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the present application. The technical scope of the present application is not limited to the contents in the specification, and must be determined according to the scope of the claims.

Claims

1. A motor stator, characterized in that: The stator core (1) includes a plurality of first core laminations (101) and a plurality of second core laminations (102). The first core laminations (101) and the second core laminations (102) each include an annular yoke (2) and a plurality of stator teeth (3) extending radially outward from the annular yoke (2). The second core lamination (102) also includes a support portion (4) located radially inside the annular yoke (2). The support portion (4) is connected to the motor shaft (13) of the outer rotor (12) motor. Several second core laminations (102) are stacked sequentially along the axial direction, and several first core laminations (101) are stacked sequentially along the axial direction at both ends of the several second core laminations (102), so that the two ends of the stator core (1) form a recessed structure (9) with a concave center.

2. The motor stator according to claim 1, characterized in that: The stacked iron core laminations are fixed together by riveting.

3. The motor stator according to claim 2, characterized in that: The first core lamination (101) and the second core lamination (102) each have a rivet point (6) protruding to the same side on the corresponding stator teeth (3), and a rivet blind hole (7) is formed on the surface of the stator teeth (3) on the other side of the rivet point (6).

4. The motor stator according to claim 3, characterized in that: Stator teeth (3) with overlapping rivet points (6) and stator teeth (3) without overlapping rivet points (6) are arranged alternately.

5. The motor stator according to claim 3, characterized in that: The stator core (1) has a third core lamination (103) at one end with a rivet point (6). The third core lamination (103) includes an annular yoke (2) and a plurality of stator teeth (3) extending radially outward from the annular yoke (2). The stator teeth (3) of the third core lamination (103) have rivet through holes (8) corresponding to the rivet point (6).

6. The motor stator according to claim 1, characterized in that: The axial depth of the sunken structure (9) is 5mm~10mm.

7. The motor stator according to claim 1, characterized in that: The radial distance from the center of the motor shaft (13) to the inner circumferential surface of the annular yoke (2) of the first iron core lamination (101) and the second iron core lamination (102) is equal.

8. The motor stator according to claim 1, characterized in that: The second core lamination (102) has a radial gap between the support portion (4) and the annular yoke portion (2), which forms a wire storage groove (10) for accommodating the connecting wire (11).

9. The motor stator according to claim 8, characterized in that: Multiple wire storage troughs (10) are arranged at intervals along the circumference.

10. The motor stator according to claim 9, characterized in that: The number of the wire storage tanks (10) is 3 to 6.

11. The motor stator according to claim 1, characterized in that: The center of the support (4) has a shaft hole (5) that mates with the motor shaft (13), and the inner circumferential surface of the shaft hole (5) has a keyway (501) that mates with the flat key on the surface of the motor shaft (13).

12. An external rotor motor, characterized in that: It includes a rotor (12), a motor shaft (13) and a motor stator as described in any one of claims 1-11, wherein the rotor (12) is located outside the motor stator and bearings (14) are provided at both ends of the motor shaft (13).

13. The external rotor motor according to claim 12, characterized in that: The inner diameter of the sunken structure (9) is larger than the outer diameter of the bearing (14), and the bearing (14) located at the input end of the motor shaft (13) is partially embedded in the sunken structure (9).

Images