Stator core and outer rotor power motor

Abstract

The utility model belongs to the technical field of permanent magnet brushless direct current motors, and particularly relates to a stator core, which comprises a stator (1), magnetic steel (2) sleeved outside the stator and a casing (3) sleeved outside the magnetic steel, 36 tooth parts (101) are arranged in the stator, an inter-tooth groove (102) is arranged between every two adjacent tooth parts, and the number of the inter-tooth grooves is 36. The external rotor motor provided by the utility model adopts the stator core, and has the following advantages: 1, the tooth part is thin, the weight is light, the winding slot fullness rate is high, and the motor efficiency is high; 2, the cogging torque of the motor is small, the starting response is fast, the pause sense is small, and the operation is smooth; the harmonic content is low, follow-up FOC vector control is facilitated, and the overall vibration and noise of the motor are smaller; 4, the edge is free of burrs after stamping and overlying, and the risk that a coil is scratched by mechanical winding after later-stage coating is avoided; and 5, riveting points are uniformly distributed at the center of each tooth part of the stator iron core, so that the riveting and stress are uniform, the motor performance is stable, and the mechanical winding does not scatter.

Description

TECHNICAL FIELD

[0001] The utility model relates to permanent magnet brushless DC motor technical field, concretely refers to a kind of outer rotor motor and the stator core for being used on it. BACKGROUND

[0002] In recent years, permanent magnet brushless DC motor with the continuous expansion of terminal customer use, product is used in more and more harsh environment, especially in recent years, the rise of heavy load plant protection unmanned aerial vehicle motor industry, it needs the above motor of this kind has high power, high efficiency, high torque, low speed, low loss, light weight, starting response speed is fast, the characteristics of smooth operation.But the present such brushless motor adopts outer rotor brushless structure, the main part of magnetic circuit composed of stator core and magnetic steel is not obviously optimized, tooth slot torque is big, starting response is slow, strong, run is not smooth.Electric machine electromotive force waveform is poor, motor torque ripple is big, easy to produce larger vibration and noise when running, and it is not conducive to subsequent FOC vector control.Moreover, the similar size core of existing market is generally 27 slot structure, stator core tooth is thick, weight is big, winding slot fullness is low, overall causes motor efficiency to be low.Stator core structure adopts single stamping forming riveting mode after, after large tonnage stamping, slot of tooth part is more sharp angle and burr, easy to cause local magnetic saturation of tooth part sharp angle, cause local temperature rise too big to influence motor performance, and subsequent riveting stacked height coating easy to form sharp point, stator core is easy to scratch enameled wire when mass mechanical winding, causes insulation to be bad.Stator core structure is less riveting point, uneven distribution, often lead to riveting uneven after stamping forming, due to not riveting or not in place, stacked height is high, loose, winding is easy to scatter piece and cause motor performance unstable situation. SUMMARY

[0003] In order to overcome the deficiencies of the prior art, one of the purposes of the present utility model is to provide a stator core.

[0004] The second purpose is to provide an outer rotor motor comprising the stator core.

[0005] The first technical solution is to provide a stator core, comprising a stator, a magnetic steel sleeve set outside the stator, a casing sleeve set outside the magnetic steel, the stator is provided with 36 teeth, and each two adjacent teeth has a tooth slot, the number of tooth slots is 36.

[0006] Preferably, the outer diameter of the stator is 119.8-120.2mm, and the inner diameter is 79.8-80.2mm; the tooth slot is trapezoidal, and the included angle between adjacent tooth slots is 10 degrees.

[0007] Preferably, the width of the slot mouth of the interdental groove is 2.2-2.6 mm, the upper width of the interdental groove is 6.8-6.9 mm, and the lower width is 5.0-5.1 mm; the tooth part is integrally formed by a tooth body and a tooth tip; the width of the tooth body is 3.2-3.5 mm, and the thickness of the tooth tip is 1.3-1.4 mm; the distance from the upper part of the interdental groove to the bottom of the interdental groove is 10.2-10.3 mm.

[0008] Preferably, the number of slots of the stator is 36 slots, the corresponding number of rotor poles is 40 poles, the number of phases is 3, and the number of interdental slots per pole per phase is 3 / 10; the pole distance included angle is 9 degrees.

[0009] Preferably, the radius of the slot bottom arc on both sides of the bottom of the interdental groove is 1.1-1.25 mm, the radius of the slot top arc on both sides of the top of the interdental groove is 0.75-0.85 mm; the radius of the end inner arc of the tooth tip is 0.75-0.85 mm, and the radius of the end outer arc is 0.75-0.85 mm.

[0010] Preferably, three positioning grooves are arranged on the inner wall of the stator, and the three positioning grooves are arranged at the radially equal division positions of the stator; the cross section of the positioning groove is arc-shaped and the length direction thereof is parallel to the axial direction of the stator; the radius of the positioning groove is 1-1.2 mm.

[0011] Preferably, a riveting hole is arranged in the tooth body of each tooth part; the riveting hole is square-shaped and arranged at the center of the tooth body, the width of the riveting hole is 0.6-0.7 mm, and the length is 2-2.4 mm; a corner arc is arranged at each of the four corners of the riveting hole, and the radius of the corner arc is 0.2-0.3 mm; the length direction of the riveting hole is consistent with the length direction of the tooth body.

[0012] Preferably, the magnetic steel is a circular body enclosed by a plurality of magnetic steel monomers; a chamfering arc is arranged at each of the four corner positions of the magnetic steel monomer, and the radius of the chamfering arc is 0.2-0.3 mm; the included angle of the arc length of the magnetic steel monomer is 6.93°-7.29°.

[0013] The first purpose technical solution is achieved: an outer rotor motor, comprising the stator core.

[0014] Technical effects: the outer rotor motor adopts the stator core, and has the following advantages:

[0015] 1, the stator adopts 36 slot design, the motor is more easy to realize low speed big torque, the stator tooth width 3.2-3.5, tooth part is thin, light in weight, winding slot full rate is high, motor efficiency is high.

[0016] 2. The main part of the magnetic circuit is optimized and designed, the width of the notch of the stator is 2.2-2.6mm, namely the stator notch coefficient K=0.21-0.25; the included angle of the arc length of the magnetic steel monomer is 6.93°-7.29°, namely the magnetic steel pole arc coefficient ai=0.77-0.81; the motor tooth slot torque is small, the starting response is fast, the jerk feeling is small, and the operation is smooth.

[0017] 3. A 40-pole design is adopted, namely the slot number q=3 / 10 per pole per phase, the winding harmonic is reduced, the subsequent magnetic steel is magnetized by a sine wave, the electromotive force waveform is smoother and more sinusoidal, the torque ripple of the motor is reduced, the harmonic content is low, which is beneficial to subsequent FOC vector control, and the overall vibration and noise of the motor are smaller.

[0018] 4. The edges of the tooth portions are uniformly treated with R-angle, and the circular arc is gradually changed, so that local magnetic saturation caused by sharp corners of the tooth portions is effectively avoided, the temperature rise is not too large to affect the performance of the motor, the edges are free of burrs after stamping and laminating, and there is no risk of scratching the wire package during mechanical winding after coating.

[0019] 5. The rivets are uniformly and centrally distributed in each tooth portion of the stator core, the riveting and stress are uniform, there is no situation that a single groove is high and loose, the performance of the motor is stable, and the mechanical winding is not scattered. DETAILED DESCRIPTION

[0020] Figure 1 It is a front view of the stator of the embodiment of the utility model;

[0021] Figure 2 It is a front view of the local structure of the stator of the embodiment of the utility model;

[0022] Figure 3 It is a front view of the stator core of the embodiment of the utility model;

[0023] Figure 4 It is a tooth slot torque curve diagram of the embodiment of the utility model;

[0024] Figure 5 It is an electromotive force waveform diagram of the embodiment of the utility model;

[0025] Figure 6 It is an electromotive force harmonic diagram of the embodiment of the utility model;

[0026] Figure 7 It is a torque harmonic diagram of the embodiment of the utility model;

[0027] Figure 8 It is a perspective view of the outer rotor motor of the embodiment of the utility model.

[0028] Reference numerals: Stator-1, Tooth-101, Tooth body-101a, Tooth tip-101b, Riveting hole-101c, Inter-tooth groove-102, Groove opening-102a, Magnet-2, Magnet unit-201, Housing-3, Outer diameter-D1, Inner diameter-D2, Angle-a, Groove bottom arc-R1, Groove top arc-R2, Pole pitch angle-bp, Arc length angle-ap, Inner arc-R3, Outer arc-R4, Positioning groove-R5, Corner arc-R6, Chamfer arc-R7. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0030] like Figures 1-3 As shown, this utility model embodiment provides a stator core, including a stator 1, a magnet 2 sleeved on the outside of the stator, and a housing 3 sleeved on the outside of the magnet. The stator has 36 teeth 101, and there is a tooth groove 102 between two adjacent teeth. The number of tooth grooves is 36, so as to achieve the effect of low speed and high torque.

[0031] The outer diameter D1 of the stator 1 is 119.8-120.2 mm, and the inner diameter D2 is 79.8-80.2 mm; the tooth groove 102 is trapezoidal in shape, and the included angle α between adjacent tooth grooves is 10 degrees, that is, α = 360 / 36 = 10 degrees.

[0032] Specifically, to reduce the cogging torque of the motor and facilitate subsequent mechanical winding, the stator core is selected with a slot coefficient K between 0.21 and 0.25, meaning the width of the slot 102a of the inter-tooth slot 102 is 2.2-2.6 mm. To improve the winding slot fill factor, reduce core weight, and increase motor efficiency, the upper width Bs1 of the inter-tooth slot is 6.8-6.9 mm, and the lower width Bs2 is 5.0-5.1 mm. In this embodiment, the tooth 101... It is integrally formed from a tooth body 101a and a tooth tip 101b; the width of the tooth body 101a is 3.2-3.5mm, and the thickness Hs0 of the tooth tip is 1.3-1.4mm; the distance Hs2 from the upper part of the tooth groove to the bottom of the tooth groove is 10.2-10.3mm; the radius of the bottom arc R1 on both sides of the bottom of the tooth groove 102 is 1.1-1.25mm, and the radius of the top arc R2 on both sides of the top of the tooth groove 102 is 0.75-0.85mm.

[0033] In order to optimize the magnetic circuit design, make the motor's tooth slot torque smaller, the electromotive force more sinusoidal, the torque ripple and the harmonic content low, the slot number of the stator 1 is 36 slots, corresponding to the rotor pole number is 40 poles, the phase number is 3, that is, the motor adopts 2P=40 pole design, the tooth-to-slot number of each pole per phase is 3 / 10; the pole pitch angle bp is 9 degrees, that is, the pole pitch angle bp=360 / 2p=9°.

[0034] In order to avoid the local magnetic saturation of the tooth tip angle, cause the excessive temperature rise to affect the motor performance, and the risk of no scratch line package after subsequent coating and mechanical winding, the tooth part adopts a rounded corner design, specifically, the radius of the inner side arc R3 of the end of the tooth tip 101b is 0.75-0.85mm, and the radius of the outer side arc R4 of the end is 0.75-0.85mm.

[0035] In order to facilitate subsequent mechanical winding positioning, three positioning grooves R5 are arranged on the inner wall of the stator 1, and the three positioning grooves are arranged at the radial equal division positions of the stator, that is, the interval angle between the adjacent two positioning grooves is 120 degrees; the cross section of the positioning groove is arc-shaped and the length direction thereof is parallel to the axial direction of the stator; the radius of the positioning groove R5 is 1-1.2mm.

[0036] In order to improve the subsequent stamping and riveting, the mechanical winding does not scatter, a single slot single rivet point centering design is adopted, that is, a riveting hole 101c is arranged in the tooth body 101a of each tooth part 101; the riveting hole is square-shaped and arranged at the center of the tooth body 101a, the width of the riveting hole is 0.6-0.7mm, and the length is 2-2.4mm; the four corner arcs R6 are arranged at the four corner positions of the riveting hole; the radius of the corner arc is 0.2-0.3mm; the length direction of the riveting hole 101c is consistent with the length direction of the tooth body 101a.

[0037] The magnetic steel 2 is a circular body surrounded by a plurality of magnetic steel monomers 201; the four corner positions of the magnetic steel monomer are provided with chamfered arcs R7, and the radius of the chamfered arc is 0.2-0.3mm; the arc length angle ap of the magnetic steel monomer is 6.93°-7.29°, that is, the pole arc coefficient ai=0.77-0.81 is optimized and selected in the design.

[0038] As shown in Figure 8 The utility model discloses a kind of outer rotor power machines, it includes the stator core of preceding.

[0039] Adopt the stator core of the utility model, tooth slot 102 torque is low, the highest point is no more than 0.025N.m, motor back electromotive force waveform is good, no obvious distortion, torque ripple is low, the 3rd harmonic, the 5th harmonic is low;As shown in Figures 4-7 .

[0040] In the above description, it needs to be explained that the terms "mounting", "connection", "connecting" and the like corresponding terms should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be direct connection, or indirect connection through intermediate medium, it can be the communication inside two components; "provided in" should be understood as "mounted, arranged", including fixed mounting, movable mounting and other mounting modes.

[0041] Obviously, the above described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The preferred embodiments of the present application are given in the drawings, but do not limit the patent scope of the present application. The present application can be realized in many different forms, and conversely, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive. Any equivalent structure made by using the content of the present application specification and drawings, directly or indirectly applied in other related technical fields, is also within the patent protection scope of the present application.

Claims

1. A stator core comprising a stator (1), a magnetic steel (2) sleeved outside the stator, a casing (3) sleeved outside the magnetic steel, characterized in that, The stator is provided with 36 tooth portions (101), and each two adjacent tooth portions has a tooth slot (102) therebetween, and the number of tooth slots (102) is 36; The width of the slot opening (102a) of the tooth slot (102) is 2.2-2.6 mm, the upper width of the tooth slot is 6.8-6.9 mm, and the lower width is 5.0-5.1 mm; the tooth portion (101) is integrally formed by a tooth body (101a) and a tooth tip (101b); the width of the tooth body (101a) is 3.2-3.5 mm, and the thickness of the tooth tip is 1.3-1.4 mm; the distance from the upper part of the tooth slot to the bottom of the tooth slot is 10.2-10.3 mm.

2. A stator core as claimed in claim 1, characterized in that The outer diameter (D1) of the stator (1) is 119.8-120.2 mm, and the inner diameter (D2) is 79.8-80.2 mm; the tooth slot (102) is in a trapezoidal shape, and the included angle (a) between adjacent tooth slots is 10 degrees.

3. A stator core as claimed in claim 2, characterized in that The number of slots of the stator (1) is 36, the corresponding number of rotor poles is 40, the number of phases is 3, and the number of tooth slots per pole per phase is 3 / 10; the pole pitch angle (bp) is 9 degrees.

4. A stator core as claimed in claim 1, characterized in that The radius of the slot bottom arc (R1) on both sides of the bottom of the tooth slot (102) is 1.1-1.25 mm, the radius of the slot top arc (R2) on both sides of the top of the tooth slot (102) is 0.75-0.85 mm, the radius of the end inner arc (R3) of the tooth tip (101b) is 0.75-0.85 mm, and the radius of the end outer arc (R4) is 0.75-0.85 mm.

5. A stator core as claimed in claim 1, characterized in that The inner wall of the stator (1) is provided with three positioning grooves (R5), and the three positioning grooves are respectively arranged at the radial equal division positions of the stator; the cross section of the positioning groove is arc-shaped, and the length direction thereof is parallel to the axial direction of the stator; the radius of the positioning groove (R5) is 1-1.2 mm.

6. A stator core as claimed in claim 1, characterized in that Each tooth portion (101) is provided with a riveting hole (101c) in the tooth body (101a); the riveting hole is square-shaped and is arranged at the center of the tooth body (101a), the width of the riveting hole is 0.6-0.7 mm, and the length is 2-2.4 mm; the four corner arcs (R6) of the riveting hole are provided with corner arcs (R6), and the radius of the corner arc is 0.2-0.3 mm; the length direction of the riveting hole (101c) is consistent with the length direction of the tooth body (101a).

7. A stator core as claimed in claim 1, characterized in that The magnetic steel (2) is a circular body enclosed by a plurality of magnetic steel monomers (201); the four corner positions of the magnetic steel monomer are provided with chamfered arcs (R7), and the radius of the chamfered arc is 0.2-0.3 mm; the included angle (ap) of the arc length of the magnetic steel monomer is 6.93°-7.29°.

8. An external rotor dynamical electric machine, characterized by, The stator core comprises the stator core according to any one of claims 1-7.

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