Brushless motor and brushless motor structure thereof

Abstract

The invention provides a brushless motor and a brushless motor structure thereof. The brushless motor comprises a stator, a rotor (201) and a motor shaft (2), among a plurality of flat-plate-shaped magnetic steels (6) which are attached to a mounting surface (71), facing a stator (101), of a rotor (201) in the radial direction and are arranged in the circumferential direction, adjacent magnetic steels (6) are directly combined, and the direct combination comprises direct contact or an integral component. Compared with a non-direct-combination structure, the magnetic performance such as the magnetic flux maximum value, the air gap magnetic induction intensity maximum value and the air gap magnetic induction intensity effective value of unit length is improved by adopting a structure that adjacent magnetic steels are directly combined.

Description

Technical Field

[0001] The present invention belongs to the technical field of motors, and specifically relates to a brushless motor and its brushless motor structure. Background Art

[0002] The patent document CN201623552U, which was published on November 03, 2010, discloses a rotor structure of an outer-rotor brushless motor. There is a gap between the magnetic steels, and injection molding or filling with fixing glue is used, that is, the magnetic steels do not directly contact each other.

[0003] The patent document CN204721125U, which was published on October 21, 2015, discloses a rotor structure of an outer-rotor brushless motor. Compared with the patent document CN201623552U, a magnetic steel groove is added, and a spacer is provided between the magnetic steels, and the magnetic steels still do not directly contact each other.

[0004] The patent document CN110165806A, which was published on August 23, 2019, discloses a rotor structure of an outer-rotor brushless motor. Compared with the spacer in the patent document CN204721125U, the rotor core is further provided with magnetic isolation grooves communicating with the magnetic steel grooves at both ends of each magnetic steel groove, and magnetic isolation filling blocks are arranged in the magnetic isolation grooves. The magnetic steels still do not directly contact each other, and the magnetic isolation filling blocks are used to further weaken the magnetic circuit relationship between the magnetic steels.

[0005] The patent document CN218071134U, which was published on December 16, 2022, improves the above patent documents. It discloses a rotor structure of an outer-rotor brushless motor. Compared with the patent documents CN201623552U, CN204721125U, and CN110165806A, a magnetic conduction ring is added between the magnetic steel and the inner side wall of the rotor housing, strengthening the magnetic circuit relationship between the magnetic steels. However, the price is that an additional magnetic conduction ring is required, and the magnetic steels are arranged between two adjacent positioning protrusions of the magnetic conduction ring and are separated from each other, and the route of direct contact between the magnetic steels is not adopted, that is, the magnetic steels still do not directly contact each other. Summary of the Invention

[0006] Aiming at the defects in the prior art, the purpose of the present invention is to provide a brushless motor and its brushless motor structure.

[0007] According to a brushless motor structure provided by the present invention, it includes: a stator 101, a rotor 201, and a motor shaft 2; the stator 101 is fixedly installed with the motor shaft 2; the rotor 201 surrounds the stator 101, and the rotor 201 is installed on the motor shaft 2 through a bearing; the winding 3 of the stator 101 is electrically connected to the lead wire 1, and the lead wire 1 extends to the outside of the motor shaft 2;

[0008] Among the multiple flat plate-shaped magnets 6 arranged circumferentially where the rotor 201 fits against the mounting surface 71 facing radially inwards towards the stator 101, the adjacent magnets 6 are directly joined, where the direct joining includes direct contact or being an integral component.

[0009] Preferably, the multiple magnets 6 are independent components, and the direct joining means that the adjacent magnets 6 in the circumferential direction are in direct contact with each other after fitting against the mounting surface 71.

[0010] Preferably, the side surfaces 60 of the adjacent magnets 6 are in direct contact; the inner surface 61 of the magnet 6 is parallel to the outer surface 62, and the side surface 60 of the magnet 6 is a convex arc surface;

[0011] Or,

[0012] The edges 610 of the inner surfaces 61 of the adjacent magnets 6 are in direct contact; the magnet 6 is a rectangular magnet, and the edge 610 refers to the right-angle structure or chamfer structure between the inner surface 61 and the side surface 60 of the magnet 6.

[0013] Preferably, the direct joining means that the multiple magnets 6 are an integral ring-shaped component and are always connected.

[0014] Preferably, the opening at one end of the rotor 201 in the axial direction allows the multiple magnets 6 of the integral component to enter the rotor 201 axially and be installed on the mounting surface 71.

[0015] Preferably, among the multiple flat plate-shaped magnets 6 arranged circumferentially where the rotor 201 fits against the mounting surface 71 facing radially inwards towards the stator 101, all or some of the adjacent magnets 6 have their side surfaces 60 directly joined;

[0016] Or,

[0017] Among the multiple flat plate-shaped magnets 6 arranged circumferentially where the rotor 201 fits against the mounting surface 71 facing radially inwards towards the stator 101, all or some of the edges 610 of the inner surfaces 61 of the adjacent magnets 6 are directly joined.

[0018] Preferably, the mounting surface 71 of the rotor 201 facing radially inwards towards the stator 101 is a plane matching the outer surface 62 of the magnet 6.

[0019] Preferably, the planes provided by the multiple mounting surfaces 71 enclose a polygon.

[0020] Preferably, the polygon is a regular polygon.

[0021] A brushless motor provided according to the present invention includes a housing and also includes the brushless motor structure as described above located in the housing.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. By adopting the structure of directly combining adjacent magnets with each other, compared with the non-direct combination structure, the magnetic properties such as the maximum value of magnetic flux per unit length, the maximum value of air-gap magnetic induction intensity, and the effective value of air-gap magnetic induction intensity are all improved. There is no need to add a magnetic conduction ring between the magnet and the inner side wall of the rotor housing.

[0024] 2. By adopting the structure of directly contacting adjacent magnets with each other, compared with the non-direct combination structure, when installing the magnets, the accuracy of the installation position of the magnets can be improved. The later-attached magnets can be accurately positioned by relying on the contact method, and when attaching the last magnet, it can be judged whether the overall installation position of each magnet is accurate by checking whether it is in direct contact with the adjacent magnets on both sides.

[0025] 3. By adopting the structure of an integral magnetic ring with an integrated structure between adjacent magnets, compared with the non-direct combination structure, it can be installed in place at one time during installation, and the installation position is more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Other features, objects, and advantages of the present invention will become more apparent by reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0027] Figure 1 It is a schematic structural diagram of the brushless motor structure provided by the present invention, showing a part of the structure of the brushless motor.

[0028] Figure 2 It is an assembly schematic diagram of the brushless motor structure provided by the present invention.

[0029] Figure 3 It is a schematic structural diagram of the rotor of the brushless motor structure provided by the present invention.

[0030] Figure 4 It is a schematic structural diagram of the rotor and magnets of the brushless motor structure provided by the present invention.

[0031] Figure 5 For Figure 4 a partial enlarged schematic diagram.

[0032] Figure 6 For Figure 4 a separate structural schematic diagram of the magnet in

[0033] Figure 7 It is a schematic structural diagram of the rotor of the brushless motor structure provided by the present invention and an annular integral magnet constituting a polygonal magnetic ring.

[0034] Figure 8 ForFigure 7 Partial enlarged schematic view

[0035] Figure 9 is Figure 7 Separate structural schematic diagram of the permanent magnet in

[0036] Figure 10 Structural schematic diagram of adjacent rectangular permanent magnets with right-angled edges

[0037] Figure 11 Structural schematic diagram of adjacent rectangular permanent magnets with chamfered edges

[0038] Figure 12 Structural schematic diagram of adjacent permanent magnets with convex arc-shaped side surfaces

[0039] Figure 13 Magnetic performance schematic diagram of directly combined adjacent permanent magnets with a flat inner wall of the rotor

[0040] Figure 14 Magnetic performance schematic diagram of directly combined adjacent permanent magnets with a curved inner wall of the rotor

[0041] Figure 15 Magnetic performance schematic diagram of non-directly combined adjacent permanent magnets with a flat inner wall of the rotor

[0042] Figure 13 and Figure 14 and Figure 15 In

[0043] A [Wb / m] represents the magnetic flux per unit length [Weber per meter]

[0044] Br represents the air-gap magnetic induction intensity, with the unit of T

[0045] Curve Info represents curve information. The abscissa of the curve represents the circumferential angle, that is, degrees

[0046] rms represents the root mean square value

[0047] max represents the maximum value

[0048] As shown in the figure:

[0049] Specific implementation manners

[0050] The present invention will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several changes and improvements can still be made. These all belong to the protection scope of the present invention.

[0051] A brushless motor provided according to the present invention includes a housing and further includes a brushless motor structure located in the housing. That is, the brushless motor structure is a part of the brushless motor. As Figure 1 , Figure 2 shown, the brushless motor structure includes: a stator 101, a rotor 201, and a motor shaft 2; the stator 101 is fixedly installed with the motor shaft 2; the rotor 201 surrounds the stator 101, and the rotor bracket 7 of the rotor 201 is installed on the motor shaft 2 through bearings, specifically using a first bearing 9 and a second bearing 11, and a retaining ring 10 is used to block between the first bearing 9 and the second bearing 11; the winding 3 of the stator 101 is installed on the stator core 5 through an upper insulating end plate 4 and a lower insulating end plate 8, and is electrically connected to a lead wire 1, and the lead wire 1 extends to the outside of the motor shaft 2.

[0052] As Figures 3 to 12 shown, among the multiple flat-shaped permanent magnets 6 arranged circumferentially on the mounting surface 71 where the rotor 201 fits radially inwardly towards the stator 101, adjacent permanent magnets 6 are directly combined, wherein the direct combination includes direct contact or being an integral part. The mounting surface 71 where the rotor 201 fits radially inwardly towards the stator 101 is a plane matching the outer surface 62 of the permanent magnet 6, and the plane has no boss or groove structure. The planes provided by the multiple mounting surfaces 71 enclose a polygon. The polygon is a regular polygon.

[0053] The preferred examples of the present invention will be described in more detail below with reference to the accompanying drawings.

[0054] In a preferred example, as Figure 4 , Figure 5 , Figure 6 shown, adjacent permanent magnets 6 are in direct contact. The multiple permanent magnets 6 are independent components, and the direct combination means that adjacent permanent magnets 6 in the circumferential direction are in direct contact with each other after fitting on the mounting surface 71.

[0055] More specifically, continuing as Figure 10 , Figure 11 shown, the permanent magnet 6 is a rectangular permanent magnet, and the edges 610 of the inner surfaces 61 of adjacent permanent magnets 6 are in direct contact; further taking Figure 10 as an example, the edge 610 refers to the right-angle structure between the inner surface 61 and the side surface 60 of the permanent magnet 6; further taking Figure 11 as an example, the edge 610 refers to the chamfer structure between the inner surface 61 and the side surface 60 of the permanent magnet 6.

[0056] In a variant example, as Figure 12 shown, the side surfaces 60 of adjacent permanent magnets 6 are in direct contact; the inner surface 61 of the permanent magnet 6 is parallel to the outer surface 62, and the side surface 60 of the permanent magnet 6 is a convex arc surface.

[0057] In another preferred example, as Figure 7 , Figure 8 , Figure 9 show that the adjacent permanent magnets 6 are an integral part, and the direct combination means that multiple permanent magnets 6 are an integral ring-shaped part and are always connected. This integral part is of a ring structure and can be installed in place at one time during installation. Refer to Figure 1 , Figure 2 . The opening at one axial end of the rotor 201 allows multiple permanent magnets 6 of the integral part to enter the rotor 201 axially and be installed on the installation surface 71. This ring structure enters the interior of the rotor 201 from the opening of the rotor 201 and fits against the installation surface 71 of the permanent magnets of the rotor 201. The permanent magnet 6 and the installation surface 71 can be fixed by gluing or snapping.

[0058] In more preferred examples, among the multiple flat permanent magnets 6 arranged circumferentially and fitting against the installation surface 71 of the stator 101 with the rotor 201 facing radially inwards, the side surfaces 60 of all or some adjacent permanent magnets 6 are directly combined. Or, among the multiple flat permanent magnets 6 arranged circumferentially and fitting against the installation surface 71 of the stator 101 with the rotor 201 facing radially inwards, the edges 610 of the inner surfaces 61 of all or some adjacent permanent magnets 6 are directly combined.

[0059] The magnetic properties of the present invention will be described below in conjunction with Figure 13 , Figure 14 , Figure 15 .

[0060] The data in Figure 13 , Figure 14 , Figure 15 are statistically summarized as follows:

[0061]

[0062]

[0063] As Figure 13 , Figure 14 shown, Figure 13 is a schematic diagram of the magnetic properties of directly combined adjacent permanent magnets with a flat inner wall of the rotor, Figure 14 is a schematic diagram of the magnetic properties of directly combined adjacent permanent magnets with a curved inner wall of the rotor. The difference between the two lies in whether the inner wall of the rotor is flat or curved. According to the above table, the magnetic properties of directly combined adjacent permanent magnets with a flat inner wall of the rotor are better than those of directly combined adjacent permanent magnets with a curved inner wall of the rotor.

[0064] Furthermore, as Figure 13 , Figure 15 shown, Figure 13Schematic diagram of magnetic properties of adjacent permanent magnets with a flat inner wall of the rotor directly combined Figure 15 Schematic diagram of magnetic properties of adjacent permanent magnets with a flat inner wall of the rotor not directly combined. The difference between the two lies in whether the adjacent permanent magnets are directly combined. According to the above table, the magnetic properties of adjacent permanent magnets with a flat inner wall of the rotor directly combined are better than those of adjacent permanent magnets with a flat inner wall of the rotor not directly combined.

[0065] In summary, from the simulation test, it can be seen that the present invention has good magnetic properties, specifically including the performance improvement of the maximum magnetic flux per unit length, the maximum air-gap magnetic induction intensity, and the effective value of the air-gap magnetic induction intensity. The structure of the present invention can make the magnetism reach the strongest. Magnetism largely determines the performance of the permanent magnet in practical applications. In motor equipment, higher magnetism means that stronger power can be output, which promotes the improvement of the motor operation efficiency and thus reduces energy consumption.

[0066] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A brushless motor structure, characterized in that: include: Stator (101), rotor (201), motor shaft (2); The stator (101) is fixedly mounted on the motor shaft (2); the rotor (201) surrounds the stator (101), and the rotor (201) is mounted on the motor shaft (2) via a bearing; The winding (3) of the stator (101) is electrically connected to the lead wire (1), and the lead wire (1) extends to the outside of the motor shaft (2); Among the plurality of flat magnetic steels (6) arranged circumferentially and abutting against the mounting surface (71) of the rotor (201) radially inwardly toward the stator (101), adjacent magnetic steels (6) are directly coupled, wherein the direct coupling includes direct contact or being an integral component.

2. The brushless motor structure according to claim 1, characterized in that: The plurality of magnetic steels (6) are independent components, and the direct connection means that the magnetic steels (6) adjacent to each other in the circumferential direction are in direct contact with each other after being attached to the mounting surface (71).

3. The brushless motor structure according to claim 2, characterized in that: The side surfaces (60) of adjacent magnetic steels (6) are in direct contact with each other; the inner surface (61) of the magnetic steel (6) is parallel to the outer surface (62), and the side surface (60) of the magnetic steel (6) is a convex arc surface; Or, The edges (610) of the inner surfaces (61) of adjacent magnetic steels (6) are in direct contact with each other; the magnetic steel (6) is a rectangular magnetic steel, and the edge (610) refers to a right-angle structure or a chamfered structure between the inner surface (61) and the side surface (60) of the magnetic steel (6).

4. The brushless motor structure according to claim 1, characterized in that: The direct connection means that the plurality of magnetic steels (6) form an integral annular component and are always connected.

5. The brushless motor structure according to claim 4, characterized in that: The opening at one axial end of the rotor (201) allows the plurality of magnetic steels (6) of the integral component to enter the rotor (201) in the axial direction and be mounted on the mounting surface (71).

6. The brushless motor structure according to claim 1, characterized in that: Among a plurality of flat-plate magnetic steels (6) arranged in a circumferential direction and attached to a mounting surface (71) of the rotor (201) radially inwardly facing the stator (101), all or a portion of the side surfaces (60) of adjacent magnetic steels (6) are directly coupled to each other; Or, Among a plurality of flat-plate magnetic steels (6) arranged circumferentially and attached to a mounting surface (71) of a rotor (201) radially inwardly toward a stator (101), edges (610) of inner surfaces (61) of all or a portion of adjacent magnetic steels (6) are directly coupled.

7. The brushless motor structure according to any one of claims 1 to 6, characterized in that: The mounting surface (71) of the rotor (201) facing radially inward toward the stator (101) is a plane that matches the outer surface (62) of the magnetic steel (6).

8. The brushless motor structure according to claim 7, characterized in that: The planes provided by the plurality of mounting surfaces (71) are enclosed to form a polygon.

9. The brushless motor structure according to claim 8, characterized in that: The polygon is a regular polygon.

10. A brushless motor, comprising a housing, characterized in that: It also comprises the brushless motor structure according to any one of claims 1 to 9 located in the housing.

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