Motor and electric toothbrush

Abstract

A motor comprises a shell, a stator and a rotor, and an accommodating space is arranged in the shell; the stator comprises a stator core, a stator winding and a plurality of stator teeth, the stator is arranged in the accommodating space, the plurality of stator teeth are arranged at intervals along the inner circumferential direction of the stator core and are provided with rotor holes, and the stator winding is wound on the stator teeth along the axial direction of the rotor holes; the rotor is arranged in the rotor hole in a penetrating manner and can rotate relative to the stator; wherein the stator tooth comprises a winding part used for winding the stator winding and a limiting part used for limiting the stator winding, one end of the winding part is connected with the inner side wall of the stator core, and the limiting part is connected to the other end of the winding part. The width of the winding part is gradually increased towards the direction of the limiting part, and the width of the limiting part is gradually increased towards the direction of the winding part. The utility model further discloses an electric toothbrush.

Description

Technical Field

[0001] This application relates to the field of electric motor technology, and more particularly to an electric motor and an electric toothbrush. Background Technology

[0002] An electric motor is a rotating device that converts electrical energy into mechanical energy. The stator of the motor is the stationary part of the motor and is mainly used to generate a rotating magnetic field. It includes a stator core and stator windings. The inner sidewall of the stator core is provided with stator teeth, and the stator windings are wound on the stator teeth.

[0003] However, the winding opening formed between the stator teeth and the inner wall of the stator core of the existing motor is relatively small, which results in the winding machine head extending only shallowly into the winding opening. This not only makes it difficult for the winding machine to wind the wire, but also easily causes the winding frame to deform, squeezing the rotor, or even jamming the rotor, making it unable to rotate. Utility Model Content

[0004] This application provides a motor and an electric toothbrush, which aims to solve at least one of the technical problems existing in the prior art.

[0005] According to a first aspect of this application, this application provides an electric motor, comprising:

[0006] A housing, wherein the interior of the housing has an accommodating space;

[0007] The stator includes a stator core, a stator winding, and a plurality of stator teeth. The stator is disposed in the accommodating space. The plurality of stator teeth are spaced apart along the inner circumferential direction of the stator core and form rotor holes. The stator winding is wound around each stator tooth along the axial direction of the rotor holes.

[0008] A rotor, which passes through the rotor hole and is rotatable relative to the stator;

[0009] The stator teeth include a winding portion for winding the stator winding and a limiting portion for limiting the stator winding. One end of the winding portion is connected to the inner wall of the stator core, and the limiting portion is connected to the other end of the winding portion. The width of the winding portion gradually increases towards the limiting portion, and the width of the limiting portion gradually increases towards the winding portion, so that the stator winding can slide along the winding portion toward the side away from the limiting portion, which is beneficial for winding the stator winding.

[0010] The stator is disposed in the accommodating space, and a plurality of stator teeth are arranged along the inside of the stator core, and the stator winding is wound on each stator tooth along the axial direction of the rotor hole;

[0011] In the motor of the embodiment of the application, the included angle between the inner side wall of the stator core and the winding part is in the range of 50 degrees to 80 degrees, so that the winding part can extend outwardly and obliquely, which is beneficial to the winding of the stator winding; and / or the included angle between the limiting part and the winding part is in the range of 130 degrees to 155 degrees, so as to increase the width of the free end of the limiting part and reduce the vibration and noise of the motor.

[0012] In the motor of the embodiment of the application, the ratio of the maximum width of the winding part to the minimum width of the winding part is not greater than 1.5, which can ensure the stability of the stator winding after being wound on the winding part and the operation performance of the motor; and / or the ratio of the maximum width of the limiting part to the minimum width of the limiting part is not greater than 3, so as to ensure the width of the free end of the limiting part and reduce the vibration and noise of the motor.

[0013] In the motor of the embodiment of the application, the width of the winding part is between 2 mm and 3 mm, so as to ensure the structural strength of the winding part and form a winding space which is beneficial to the winding of the stator winding; and / or the width of the limiting part is between 0.3 mm and 1.5 mm, which can not only ensure the connection strength of the limiting part and the winding part, but also make the magnetic field strength in the limiting part more uniform, reduce the iron loss and improve the efficiency.

[0014] In the motor of the embodiment of the application, the included angle between the inner side wall of the stator core and the winding part is in the range of 50 degrees to 80 degrees, so that the winding part can extend outwardly and obliquely, which is beneficial to the winding of the stator winding; and / or the included angle between the limiting part and the winding part is in the range of 130 degrees to 155 degrees, so as to increase the width of the free end of the limiting part and reduce the vibration and noise of the motor.

[0015] In the motor of the embodiment of the application, the side of the limiting part away from the winding part is provided with an auxiliary groove which extends along the axial direction of the stator core, so as to reduce the cogging torque of the motor and improve the stability of the motor.

[0016] In the motor of the embodiment of the application, the stator further comprises a winding frame having a winding slot, the winding frame is arranged at both ends of the stator core, the stator winding is at least partially wound in the winding slot, and the height of the bottom of the winding slot gradually increases in the direction of the center of the stator core, so that the stator winding can slide along the inclined height of the bottom of the winding slot towards the side away from the limiting part.

[0017] In the motor of the embodiment of the application, the winding frame comprises an outer support and an inner support arranged side by side, the outer support is connected with the inner side wall of the stator core, and the inner support is connected with the limiting part.

[0018] The connecting plate is inclined upward or outward from the outer support to the inner support, so that the stator winding on the connecting plate can slide along the inclination trend of the connecting plate towards the side away from the limiting portion.

[0019] In the motor of the embodiment of the application, the inner support has two arc-shaped sections on both sides thereof, which are bent towards the center of the stator core, and the thickness of the arc-shaped sections is less than that of the bent portion of the inner support, so that the bobbin has sufficient strength and will not be easily deformed or damaged under stress.

[0020] In the motor of the embodiment of the application, the inner support is provided with an abutting groove, which abuts against the end surface of the limiting portion, so as to enhance the extrusion resistance of the bobbin and avoid the bobbin from being deformed and inclined towards the center of the stator core.

[0021] In the motor of the embodiment of the application, the inner side of the limiting portion is recessed outward to form a first arc-shaped groove, and the inner side of the inner support is recessed outward to form a second arc-shaped groove, and the diameter of the second arc-shaped groove is greater than that of the first arc-shaped groove, so that the limiting portion and the inner support can be arranged circumferentially to form a circumferential matching surface matched with the rotor, and the inner support will not affect the rotation of the rotor.

[0022] In the motor of the embodiment of the application, the projection of the second arc-shaped groove towards the limiting portion covers at least the auxiliary groove of the limiting portion, so as to ensure that the outer support and the inner support can form a winding space for limiting the stator winding, and also ensure that the inner support will not affect the rotation of the rotor.

[0023] In the motor of the embodiment of the application, the bobbin is made of insulating material, so as to support the stator winding and insulate the stator winding from the bobbin.

[0024] In the motor of the embodiment of the application, the stator core comprises a plurality of stator core pieces made of silicon steel sheets, and each stator core piece is provided with the stator tooth. The stator core pieces are fixed together by the stator winding after being stacked, which can effectively reduce the iron loss of the stator core, improve the efficiency of the motor, and reduce the temperature rise of the motor.

[0025] According to the second aspect of the application, the application further provides an electric toothbrush, which comprises a brush head and a handle shell, the handle shell is provided with the motor described above, and the output shaft of the motor penetrates out of the handle shell and is connected with the brush head to control the movement of the brush head.

[0026] The technical solutions provided in this application embodiment can include the following beneficial effects: This application designs a stator, a motor, and an electric toothbrush, including a winding part for winding a stator winding and a limiting part for limiting the stator winding. The width of the winding part is configured to gradually increase in the direction toward the limiting part, and the width of the limiting part is configured to gradually increase in the direction toward the winding part, so that the stator winding can slide along the winding part toward the side away from the limiting part, which is beneficial to the winding of the stator winding, improves the efficiency of the stator winding, solves the problem that the winding machine is not convenient for winding due to the small winding opening, and thus improves the manufacturing efficiency of the motor.

[0027] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of an electric motor provided in one embodiment of this application;

[0030] Figure 2 yes Figure 1 A cross-sectional view of the motor at the first angle;

[0031] Figure 3 yes Figure 1 A cross-sectional view of the motor at the second angle;

[0032] Figure 4 yes Figure 1 An exploded view of the motor in the diagram;

[0033] Figure 5 yes Figure 4 A schematic diagram of the stator structure in the diagram;

[0034] Figure 6 yes Figure 4 A schematic diagram of the stator exploded in the middle;

[0035] Figure 7 yes Figure 4 A cross-sectional view of the stator at the first angle;

[0036] Figure 8 yes Figure 4 A cross-sectional view of the stator at the second angle;

[0037] Figure 9is a partial exploded view of the stator in Figure 4

[0038] Figure 10 is a structural view of the bobbin in Figure 4

[0039] BRIEF DESCRIPTION OF DRAWINGS

[0040] 100, stator;

[0041] 10, stator core; 11, stator tooth; 111, winding portion; 112, limiting portion; 1121, auxiliary slot; 1122, abutting surface; 12, core body;

[0042] 20, stator winding;

[0043] 30, bobbin; 31, inner support; 31a, arc segment; 31a, main body segment; 311, abutting slot; 32, outer support; 33, connecting plate;

[0044] 200, rotor;

[0045] 300, housing. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0047] It should also be understood that the terms used in the specification of the present application are only for the purpose of describing specific embodiments of the present application in the description of the present application. It should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise explicitly and specifically limited. ​​

[0048] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0049] like Figures 1 to 3 As shown, according to one embodiment of this application, this application provides an electric motor, which includes a housing 300, a rotor 200 and a stator 100. The housing 300 has an accommodating space inside, the stator 100 is disposed in the accommodating space, and the rotor 200 is disposed in the stator 100 and can cooperate with the stator 100 to provide a power source for the motor.

[0050] In one alternative implementation, such as Figures 3 to 6 As shown, the stator 100 includes a stator core 10 and a stator winding 20. The stator winding 20 is wound on the stator core 10 so that the stator 100 can generate a magnetic field when the stator winding 20 is energized, thereby driving the rotor 200 to rotate. The stator core 10 includes multiple stator teeth 11 and a hollow core body 12. The multiple stator teeth 11 are spaced apart along the inner circumference of the core body 12 and form rotor holes. The stator winding 20 is wound on the stator teeth 11 along the axial direction of the rotor holes. The rotor 200 passes through the rotor holes and can rotate relative to the stator 210. The stator teeth 11 can provide a certain limiting effect on the stator winding 20, ensuring that the stator winding 20 is securely mounted on the stator core 10 and preventing the stator winding 20 from detaching from the stator core 10.

[0051] In one alternative implementation, such as Figures 7 to 9 As shown, the stator tooth 11 includes a winding portion 111 and a limiting portion 112. The winding portion 111 is used for winding the stator winding 20, and the limiting portion 112 is used to limit the stator winding 20. One end of the winding portion 111 is connected to the inner wall of the stator core 10, and the limiting portion 112 is connected to the other end of the winding portion 111. This allows the inner wall of the stator core 10, the winding portion 111, and the limiting portion 112 to enclose a winding space for limiting the stator winding 20. This allows the stator winding 20 to be confined within the winding space, thereby allowing the stator winding 20 to be wound and covered on the outside of the winding portion 111, which is beneficial for the winding of the stator winding 20.

[0052] In the embodiment, the width of the winding portion 111 gradually increases towards the direction of the limiting portion 112, and the width of the limiting portion 112 gradually increases towards the direction of the winding portion 111, which not only ensures the connection strength between the winding portion 111 and the limiting portion 112, but also enables the wires of the stator winding 20 to slide along the winding portion 111 towards the side away from the limiting portion 112 when the stator winding 20 is wound, so that the wires of the stator winding 20 can be reasonably arranged on the winding portion 111, avoiding disordered arrangement and increasing winding difficulty, which is beneficial to the winding of the stator winding 20. In addition, the structure design of the limiting portion 112 can also gradually increase the magnetic resistance of the limiting portion 112 from the winding portion 111 to the free end of the limiting portion 112, so as to ensure that the motor runs more smoothly and starts more reliably.

[0053] For example, in order to effectively reduce the overall size of the stator 100 and reduce the resistance of the stator 100 under the premise that the winding space size is fixed, the distance S between the free end of the limiting portion 112 and the core body 12 is very small (as shown in Figure 7 That is to say, when the stator winding 20 is wound on the winding portion 111 by a winding machine, the head of the winding machine is limited by the size of the slot formed between the limiting portion 112 and the core body 12, and cannot extend to the bottom of the winding portion 111, so that the wires of the stator winding 20 can only be concentrated on one side of the winding portion 111 close to the limiting portion 112 when the head is winding, and the whole winding portion 111 cannot be completely covered, which is easy to press the limiting portion 112, even to separate from the limiting portion 112 or to press the winding frame 30 on the stator core 10, so that the winding frame 30 deforms towards the center direction of the stator core 10, presses the rotor 200 or makes the rotor 200 stuck, which affects the service life of the motor.

[0054] In an optional embodiment, the width of the winding portion 111 gradually linearly increases from the inner side wall of the stator core 10 towards the direction of the limiting portion 112, so that the wires of the stator winding 20 can slide along the winding portion 111 towards the side away from the limiting portion 112 during winding, thereby avoiding being concentrated on one side of the winding portion 111 close to the limiting portion 112, and facilitating the winding of the stator winding 20.

[0055] In an optional embodiment, the width of the limiting portion 112 gradually linearly increases from the free end of the limiting portion 112 towards the direction of the winding portion 111, so that the magnetic resistance of the limiting portion 112 gradually increases from the winding portion 111 to the free end of the limiting portion 112, thereby ensuring that the motor runs more smoothly and starts more reliably.

[0056] In an optional embodiment, the included angle β between the inner side wall of the stator core 10 and the winding portion 111 is in the range of 50 degrees to 80 degrees (as shown in Figure 9As shown in the drawings, the winding part 111 can be outwardly inclined to extend, so that the wires of the stator winding 20 can slide along the winding part 111 during winding to move away from the side of the limiting part 112, thereby avoiding being concentrated on the side of the winding part 111 close to the limiting part 112, and facilitating the winding of the stator winding 20.

[0057] In an optional embodiment, the included angle a between the limiting part 112 and the winding part 111 is in the range of 130 degrees to 155 degrees (as shown in the drawings), and under the premise that the size of the connection between the limiting part 112 and the winding part 111 is fixed, the width of the free end of the limiting part 112 can be effectively increased, the magnetic field distribution of the stator 100 is more uniform, the harmonics are reduced, the loss is reduced, the efficiency is improved, and the vibration and noise of the motor are also reduced. Figure 9

[0058] In an optional embodiment, the ratio of the maximum width D2 of the winding part 111 to the minimum width D1 of the winding part 111 is not greater than 1.5 (as shown in the drawings), which can not only ensure the stability of the stator winding 20 after being wound on the winding part 111, but also ensure the operating performance of the motor, so that the magnetic field distribution of the stator core 10 is more uniform, and the rotor 200 is less likely to vibrate and produce noise under the action of strong magnetic force after the stator winding 20 is energized, thereby reducing the vibration and noise of the motor. Figure 8

[0059] In an optional embodiment, the ratio of the maximum width L1 of the limiting part 112 to the minimum width L2 of the limiting part 112 is not greater than 3, so that the width of the free end of the limiting part 112 can be ensured under the premise that the size of the connection between the limiting part 112 and the winding part 111 is fixed, thereby reducing the vibration and noise of the motor.

[0060] In an optional embodiment, the width of the winding part 111 is between 2 mm and 3 mm, so as to ensure the structural strength of the winding part 111 and form a winding space conducive to winding of the stator winding 20, thereby controlling the motor fluctuation within a reasonable range and effectively improving the performance of the motor. The width of the winding part 111 and the width of the winding space both have a great influence on the speed fluctuation of the motor, and the width of the winding part 111 is controlled to be between 2 mm and 3 mm, so as to control the motor fluctuation within a reasonable range and effectively improve the performance of the motor.

[0061] In an optional embodiment, the width of the limiting part 112 is between 0.3 mm and 1.5 mm, which can not only ensure the connection strength of the limiting part 112 and the winding part 111, but also ensure the structural strength of the free end of the limiting part 112, so that the magnetic field strength in the limiting part 112 is more uniform, the iron loss is reduced, and the efficiency is improved.

[0062] ​​In an optional embodiment, the free end of the limiting portion 112 has a minimum distance S from the inner side wall of the stator core 10, which is not less than the maximum width of the limiting portion 112 and not greater than the minimum width of the winding portion 111, so as to effectively reduce the overall size of the stator 100 under the condition that the winding space size is fixed; at the same time, the magnetic field leakage can be reduced, the efficiency can be improved, the harmonics can be reduced, and the pulsating torque can be reduced.

[0063] In an optional embodiment, the side of the limiting portion 112 away from the winding portion 111 is provided with an auxiliary slot 1121 extending along the axial direction of the stator core 10, so as to reduce the cogging torque of the motor and improve the stability of the motor.

[0064] In an optional embodiment, the stator 100 further comprises a winding frame 30 having a winding slot, the winding frame 30 is arranged at both ends of the stator core 10, and the stator winding 20 is at least partially wound in the winding slot. Wherein, the bottom height of the winding slot gradually increases along the center direction of the stator core 10, so that the stator winding 20 can slide along the inclined height of the bottom of the winding slot towards the side away from the limiting portion 112, avoiding extrusion to the inner side of the winding frame 30, deforming the winding frame 30 towards the center direction of the stator core 10, extruding the rotor 200 or causing the rotor 200 to be stuck, and affecting the service life of the motor.

[0065] In an optional embodiment, as shown in Figures 8 to 9 The winding frame 30 comprises an outer support 32 and an inner support 31 arranged side by side, the outer support 32 is connected with the inner side wall of the stator core 10, and the inner support 31 is connected with the limiting portion 112. Wherein, the outer support 32 and the inner support 31 are connected with a connecting plate 33, the connecting plate 33 is inclined upward or outward from the outer support 32 to the inner support 31, so that the stator winding 20 can slide along the inclined trend of the connecting plate 33 towards the side away from the limiting portion 112, avoiding extrusion to the inner side of the winding frame 30, deforming the winding frame 30 towards the center direction of the stator core 10, extruding the rotor 200 or causing the rotor 200 to be stuck, and affecting the service life of the motor.

[0066] In an optional embodiment, the inner support 31 has an arc-shaped segment 31a bent towards the center of the stator core 10 at both sides, the thickness of the arc-shaped segment 31a is less than the thickness of the bent portion of the inner support 31, so that the winding frame 30 has sufficient strength and will not be easily deformed or damaged under stress.

[0067] Exemplarily, the inner support 31 has a main body section 31a and two arc-shaped sections 31a connected to two sides of the main body section 31a and extending in directions away from each other, and the arc-shaped sections 31a are symmetrically arranged with respect to the center line of the stator tooth 11. The thickness of the arc-shaped sections 31a and the main body section 31a is less than the thickness of the arc-shaped sections 31a and the main body section 31a at the connection positions, so as to ensure the structural strength of the bobbin 30 and prevent the bobbin 30 from being easily deformed or damaged under stress.

[0068] In an optional embodiment, the inner support 31 is provided with an abutting groove 311 abutting against the end surface of the limiting portion 112, so as to enhance the extrusion resistance of the bobbin 30 and prevent the bobbin 30 from being tilted and deformed towards the center of the stator core 10. The side of the limiting portion 112 facing the bobbin 30 is provided with an abutting surface 1122, and the abutting groove 311 is abutted against the abutting surface 1122, so that the bobbin 30 can be supported at multiple positions by the stator tooth 11 and the abutting surface 1122 of the limiting portion 112, the extrusion resistance of the bobbin 30 is increased, and the bobbin 30 is prevented from being tilted and deformed towards the center of the stator core 10.

[0069] In an optional embodiment, the inner side of the limiting portion 112 is outwardly recessed to form a first arc-shaped groove, and the inner side of the inner support 31 is outwardly recessed to form a second arc-shaped groove, the diameter of the second arc-shaped groove is greater than the diameter of the first arc-shaped groove, so that the limiting portion 112 and the inner support 31 can be arranged in a circumferential direction to form a circumferential matching surface matched with the rotor 200, and the rotation of the rotor 200 is ensured not to be affected by the inner support 31.

[0070] In an optional embodiment, the projection of the second arc-shaped groove towards the limiting portion 112 covers at least the auxiliary groove 1121 of the limiting portion 112, so as to ensure that the winding space for limiting the stator winding 20 can be formed between the outer support 32 and the inner support 31, and the rotation of the rotor 200 is ensured not to be affected by the inner support 31.

[0071] In an optional embodiment, the bobbin 30 is made of an insulating material, so as to support the stator winding 20 and insulate the stator winding 20 from the bobbin 30, and the eddy current loss can be reduced when the stator winding 20 is energized.

[0072] In an alternative embodiment, the stator core 10 comprises a plurality of stator 100 cores made of silicon steel sheets, the plurality of stator 100 cores are stacked along the axial direction of the stator 100, and each stator 100 core is provided with a stator tooth 11. The stacked stator 100 cores are fixed together by the stator winding 20, which can effectively reduce the iron loss of the stator core 10, improve the efficiency of the motor, and reduce the temperature rise of the motor.

[0073] As shown in Figures 1 to 10 According to another embodiment of the present application, the present application also provides an electric toothbrush, which comprises a brush head and a handle shell, the handle shell is provided with the above-mentioned motor, and the output shaft of the motor penetrates out of the handle shell for connection with the brush head.

Claims

1. An electric machine characterized in that, The application relates to a motor, comprising: a shell, an inner part of the shell being provided with a containing space; a stator, the stator comprising a stator core, a stator winding and a plurality of stator teeth, the stator being arranged in the containing space, the plurality of stator teeth being arranged along the inner circumferential direction of the stator core and being provided with a rotor hole, the stator winding being arranged on each of the stator teeth along the axial direction of the rotor hole; a rotor, the rotor being arranged in the rotor hole and being capable of rotating relative to the stator; wherein the stator teeth comprise a winding part for winding the stator winding and a limiting part for limiting the stator winding, one end of the winding part being connected with the inner side wall of the stator core, the limiting part being connected with the other end of the winding part, the width of the winding part gradually increasing towards the limiting part, and the width of the limiting part gradually increasing towards the winding part.

2. The electric machine of claim 1, wherein, The width of the winding part gradually linearly increases from the inner side wall of the stator core towards the limiting part; and / or, the width of the limiting part gradually linearly increases from the free end of the limiting part towards the winding part.

3. The electric machine of claim 1, wherein, The ratio of the maximum width of the winding part to the minimum width of the winding part is not greater than 1.5; and / or, the ratio of the maximum width of the limiting part to the minimum width of the limiting part is not greater than 3.

4. The electric machine of claim 1 or 3, characterized in that The width of the winding part is between 2 mm and 3 mm; and / or, the width of the limiting part is between 0.3 mm and 1.5 mm.

5. The electric machine of claim 1, wherein, The included angle between the inner side wall of the stator core and the winding part is in the range of 50 degrees to 80 degrees; and / or, the included angle between the limiting part and the winding part is in the range of 130 degrees to 155 degrees.

6. The electric machine of claim 1, wherein, The side of the limiting part away from the winding part is provided with an auxiliary groove, the auxiliary groove extending along the axial direction of the stator core.

7. The electric machine of claim 1, wherein, The stator further comprises a winding frame with a winding groove, the winding frame being arranged at both ends of the stator core, the stator winding being at least partially arranged in the winding groove, and the bottom height of the winding groove gradually increasing along the central direction of the stator core.

8. The electric machine of claim 7, wherein, The winding frame comprises a side-by-side arranged outer support and an inner support, the outer support being connected with the inner side wall of the stator core, and the inner support being connected with the limiting part; wherein the outer support and the inner support are connected with a connecting plate, the connecting plate being inclined upward or outward from the outer support to the inner support.

9. The electric machine of claim 8, wherein, Both sides of the inner support are provided with an arc-shaped section bent towards the center of the stator core, the thickness of the arc-shaped section being smaller than the thickness of the bent part of the inner support.

10. The electric machine of claim 8, wherein, The inner side of the inner support is provided with an abutting groove, the abutting groove abutting with the end surface of the limiting part.

11. The electric machine of claim 8, wherein, The inner side of the limiting part is outwardly recessed to form a first arc-shaped groove, the inner side of the inner support is outwardly recessed to form a second arc-shaped groove, and the diameter of the second arc-shaped groove is greater than that of the first arc-shaped groove.

12. The electric machine of claim 11, wherein, The projection of the second arc-shaped groove towards the limiting part covers at least the auxiliary groove of the limiting part.

13. The electric machine of claim 7, wherein, The winding frame is made of insulating material.

14. The electric machine of claim 1, wherein, The stator core comprises a plurality of stator chips made of silicon steel sheets, and each of the stator chips is provided with the stator teeth.

15. An electric toothbrush, characterized by A brush head and a handle shell, the handle shell is provided with the motor as claimed in any one of claims 1 to 14, the output shaft of the motor is penetrated from the handle shell for connecting with the brush head.

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