Motor and electric toothbrush

Abstract

The utility model discloses a motor and an electric toothbrush. The motor comprises a housing, a stator assembly and a rotor assembly. A containing space is formed in the machine shell. The stator assembly is arranged in the accommodating space and comprises an excitation piece and a magnetic piece. The excitation piece comprises an excitation frame and a coil winding. The excitation frame surrounds to form an excitation space. The excitation frame comprises a winding part and a limiting part which are connected, and the coil winding is wound around the winding part. The rotor assembly is arranged in the excitation space and comprises a rotor iron core, and the rotor iron core is used for being magnetized under excitation of a magnetic field generated by the excitation piece and generating acting force with the magnetic piece so as to rotate in the excitation space in a reciprocating mode. Wherein the limiting part is located in the excitation space, and the limiting part is used for limiting the reciprocating rotation of the rotor iron core. The rotor is limited through the arrangement of the limiting part, and the situation that the rotor rotates out of a preset range, and consequently the brush head of the electric toothbrush stimulates sensitive parts of the oral cavity of a user and even damages oral cavity tissue of the user is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric machines, and more particularly, to an electric machine and an electric toothbrush. BACKGROUND

[0002] At present, the application of electric toothbrushes has become more and more extensive. The electric toothbrush drives the brush head to produce a sweeping vibration motion through the sweeping vibration motion of the electric machine. The sweeping vibration motion can be considered as a combination of high-frequency vibration and low-frequency sweeping motion. The high-frequency vibration can instantaneously decompose toothpaste into fine foam and help the bristles to extend into the tooth gaps to clean the residues or tartar in the tooth gaps. The low-frequency sweeping motion can make the entire brush head swing in a larger angle range to improve the cleaning area of the brush head. In addition, the high-frequency vibration of the bristles can promote the blood circulation of the oral cavity and has a massaging effect on the gum tissue. In the current electric toothbrush, the controller of the electric machine needs to control the rotor to produce a sweeping vibration motion on the one hand, and to control the rotor to be within a specific angle range on the other hand. Otherwise, the rotor may rotate to outside the preset angle range, and then the brush head also rotates to outside the preset angle range, which may cause the brush head or the bristles to stimulate the sensitive parts of the user's oral cavity, and even damage the oral tissue of the user. SUMMARY

[0003] The present application provides an electric machine and an electric toothbrush.

[0004] The electric machine of the present application comprises a machine shell, a stator assembly and a rotor assembly. The machine shell has an accommodating space formed inside. The stator assembly is arranged in the accommodating space and comprises an excitation member and a magnetic member. The excitation member comprises an excitation frame and a coil winding. The excitation frame surrounds an excitation space. The excitation frame comprises a winding portion and a limiting portion connected with each other, and the coil winding is wound around the winding portion. The rotor assembly is arranged in the excitation space and comprises a rotor core. The rotor core is magnetized under the excitation of the magnetic field generated by the excitation member and generates a force with the magnetic member to reciprocate in the excitation space. The limiting portion is located in the excitation space, and the limiting portion is used to limit the reciprocation of the rotor core.

[0005] In the electric machine and the electric toothbrush of the present application, the rotor core is arranged in the excitation space, and the excitation space is formed around the excitation frame. Therefore, the excitation frame also surrounds the rotor core. The excitation frame comprises a limiting portion. When the rotor core rotates to an angle that is too large and may rotate to outside the preset range, the limiting portion can abut against the rotor core to provide mechanical limiting for the rotor core, so as to avoid the rotor core from rotating to outside the preset range. In this way, the brush head is also avoided from rotating to outside the preset range to stimulate the sensitive parts of the user's oral cavity, and even damage the oral tissue of the user.

[0006] In some embodiments, the rotor assembly further comprises a rotor shaft, the rotor core is sleeved on the rotor shaft, and the rotor core comprises two opposite end portions distributed along a radial direction of the rotor shaft, and the size of the excitation space at the limiting portion along a circumferential direction of the rotor shaft increases from the rotor shaft to the end portions.

[0007] The size of the excitation space at the limiting portion along the circumferential direction of the rotor shaft increases, which provides space for the rotor core, and thus the rotatable angle of the rotor core is increased.

[0008] In some embodiments, the rotor core comprises a core body and a protruding portion protruding from the core body in a rotating direction of the rotor core. The protruding portion is used to abut against the limiting portion.

[0009] The protruding portion is used to abut against the limiting portion, so that the core body does not abut against the limiting portion, and thus the rotor core only partially abuts against the limiting portion, which can reduce the abnormal sound of the motor.

[0010] In some embodiments, the protruding portion is arranged at an end portion of the core body.

[0011] The protruding portion is arranged at the end portion of the core body, so that the protruding portion can stop the core body from rotating out of a preset range under a smaller force, and the protruding portion and the limiting portion are protected from being subjected to excessive force.

[0012] In some embodiments, a limiting groove is arranged on the limiting portion, and the protruding portion enters the limiting groove to cooperate with the limiting groove when the rotor core rotates in the excitation space.

[0013] The protruding portion cooperates with the limiting groove, which can increase the contact area at the contact position of the protruding portion and the limiting portion, so that the pressure on the limiting portion or the protruding portion is dispersed, and the limiting portion or the protruding portion is protected.

[0014] In some embodiments, a buffer is arranged on at least one of the protruding portion and the limiting portion, and the buffer is used to buffer the impact force between the protruding portion and the limiting portion.

[0015] The buffer is arranged to reduce the impact force between the protruding portion and the limiting portion when the protruding portion and the limiting portion collide, so that the rotor core and the excitation frame are protected from being damaged.

[0016] In some embodiments, the rotor assembly further comprises a rotating shaft, and the rotor core is sleeved on the rotating shaft. The excitation member comprises a first excitation member and a second excitation member. The first excitation member and the second excitation member are connected in the radial direction of the rotating shaft, and the first excitation member and the second excitation member jointly enclose the excitation space.

[0017] The first excitation member and the second excitation member can be controlled separately, so that the control accuracy of the rotor core can be improved.

[0018] In some embodiments, the excitation member comprises a connecting portion. The connecting portion of the first excitation member is provided with a first combining portion, and the connecting portion of the second excitation member is provided with a second combining portion. The first combining portion cooperates with the second combining portion to connect the first excitation member and the second excitation member.

[0019] The first combining portion and the second combining portion can cooperate, so that a connecting effect can be generated between the first excitation member and the second excitation member, and relative movement of the first excitation member and the second excitation member is avoided, thereby improving the reliability of the motor operation.

[0020] In some embodiments, the first combining portion comprises at least two first combining portions. Two of the at least two first combining portions are respectively arranged at two opposite corners of the connecting portion, and the second combining portion is arranged in one-to-one correspondence with the first combining portion.

[0021] The distance between the two opposite corners is often the farthest distance on the geometric surface. Therefore, two of the at least two first combining portions are respectively arranged at two opposite corners of the connecting portion, i.e., the two first combining portions are arranged as far away from each other as possible, so that the effect of preventing relative rotation of the first excitation member and the second excitation member is improved.

[0022] In some embodiments, the first excitation member and the second excitation member enclose a through hole, the rotor core is fixedly connected with the rotating shaft, the rotating shaft passes through the through hole and rotates in the through hole.

[0023] The through hole is enclosed by the first excitation member and the second excitation member, so that a hole does not need to be punched in the first excitation member or the second excitation member to form the through hole, thereby reducing the manufacturing difficulty and cost of the excitation member.

[0024] In some embodiments, the rotor assembly further comprises a rotating shaft, and the rotor core is sleeved on the rotating shaft. In a direction perpendicular to an excitation direction in which the excitation member generates a magnetic field and perpendicular to an extension direction of the rotating shaft, the excitation member cooperates with the inner wall of the housing.

[0025] The magnet and the inner wall of the casing are matched, so that the magnet and the casing are prevented from moving relative to each other, thereby improving the stability of the magnet.

[0026] In some embodiments, the casing is provided with a mounting opening for the stator assembly and the rotor assembly to enter the casing. The inner wall surface of the casing matched with the magnet is a matching surface, which is a plane, and the matching surface is connected with the mounting opening.

[0027] The matching surface is a plane, so that the magnet can slide into the casing under the guidance of the matching surface during installation, thereby facilitating the installation of the magnet.

[0028] In some embodiments, the motor further comprises a mounting member. The magnetic member is mounted on the mounting member, and the mounting member is matched with the casing in the magnetization direction of the magnetic field generated by the magnet.

[0029] The mounting member is matched with the casing and the magnet at the same time, and the magnetic member is also mounted on the mounting member, so that the stator assembly and the casing of the motor form a firm whole, thereby improving the stability of the motor in operation.

[0030] In some embodiments, the mounting member is provided with a clamping groove, and the magnetic member is arranged in the clamping groove.

[0031] The groove wall of the clamping groove can provide a limiting effect for the magnetic member, thereby improving the stability of the magnetic member.

[0032] In some embodiments, the rotor core comprises a plurality of sheets, and the plurality of sheets are stacked to form the rotor core.

[0033] There can be contact resistance between the plurality of sheets, or the surface of the sheets has an oxide layer to increase the resistance between the sheets, so that the overall resistance of the rotor core is increased, thereby reducing the eddy current loss in the rotor core.

[0034] The electric toothbrush of the embodiments of the present application comprises the motor and the brush head of any of the above-mentioned embodiments, and the motor is connected with the brush head.

[0035] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0036] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description, taken in conjunction with the following drawings in which:

[0037] Figure 1 is a perspective assembly view of an electric motor of some embodiments of the present application;

[0038] Figure 2 is a perspective exploded view of the electric motor shown in Figure 1

[0039] Figure 3 is a front view of the electric motor shown in Figure 1

[0040] Figure 4 is a cross-sectional view of the electric motor shown in Figure 3

[0041] Figure 5 is a cross-sectional view of the electric motor shown in Figure 3

[0042] Figure 6 is a right view of the electric motor shown in Figure 1

[0043] Figure 7 is a cross-sectional view of the electric motor shown in Figure 6

[0044] Figure 8 is a perspective assembly view of a first field, a second field, a mounting member, a magnetic member, and a rotating shaft of the electric motor shown in Figure 1

[0045] Figure 9 is a perspective assembly view of a field and a rotor core of the electric motor shown in Figure 1

[0046] Figure 10 is a perspective exploded view of a coil winding of the field of the electric motor shown in Figure 1

[0047] Figure 11 is a perspective assembly view of an electric toothbrush of some embodiments of the present application.

[0048] Explanation of main component symbols:

[0049] Electric toothbrush 1000;

[0050] Electric motor 100; brush head 200;

[0051] Housing 10; accommodation space 11; mounting port 12; mating surface 13;

[0052] ​​​​​​​​​End cap 20;

[0053] Stator assembly 40; magnetic piece 41; excitation piece 42; first excitation piece 42a; second excitation piece 42b; excitation frame 421, winding part 421a, limiting part 421b, connecting part 421c; coil winding 422; excitation space 423; through hole 424;

[0054] Rotor assembly 50; rotating shaft 51; rotor core 52, core main body 52a, protruding part 52b, end part 52c;

[0055] Mounting piece 60; clamping groove 61;

[0056] First bearing 71; second bearing 72. DETAILED DESCRIPTION

[0057] In order to make the above-mentioned purposes, features and advantages of the present application more apparent and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, a large number of specific details are set forth in order to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application, so the present application is not limited to the specific embodiments disclosed below.

[0058] In order to decompose toothpaste and help the bristles of the electric toothbrush enter the gaps of the user's teeth to clean the teeth, the brush head of the electric toothbrush needs to vibrate with a small amplitude and a high frequency, for example, the vibration range is 0.5° to 1°; in order to make the cleaning range of the brush head larger, the brush head of the electric toothbrush also needs to swing with a large amplitude, for example, the vibration range is 25° to 35°, so that the brush head can clean more tooth areas in the growth direction of the teeth. In order to achieve the above effects at the same time, the brush head of the electric toothbrush can vibrate and swing at the same time, that is, the brush head performs a sweep vibration motion. The rotor of the acoustic motor needs to perform a sweep vibration motion to drive the brush head to realize the sweep vibration motion, and the drive controller of the acoustic motor needs to load a low-frequency sweep driving current and a high-frequency vibration driving current on the coil winding of the acoustic motor at the same time, which is already a high requirement for the controller of the acoustic motor itself, but the drive controller also needs to avoid the rotor of the acoustic motor from rotating to a preset range, for example, when the rotor needs to swing in a range of 30°, if the rotor rotates to 40° or even 50°, it is considered that the rotor has rotated to the outside of the preset range. When the rotor rotates to the outside of the preset range, the brush head driven by the rotor will brush the area in the oral cavity with a too large range, for example, the cheek mucosa or the sublingual area, etc. These sensitive parts are more fragile than the gums, and the brushing force suitable for the gums may stimulate or even damage these sensitive parts.

[0059] To avoid the bristles of the brush head stimulating sensitive parts of the user's oral cavity or even damaging the user's oral tissue, embodiments of the present application provide an electric motor 100 Figure 1 and an electric toothbrush 1000 Figure 11 . It can be understood that the electric toothbrush 1000 at least includes the same beneficial effects as the electric motor 100, and thus the beneficial effects of the electric toothbrush 1000 are described below in relation to the beneficial effects of the electric motor 100. The electric toothbrush 1000 can further include a housing, the electric motor 100 is installed in the housing, the brush head 200 is installed on the outside of the housing, and the electric motor 100 is connected to the brush head 200, so that the electric motor 100 can control the brush head 200 to perform sweep vibration.

[0060] Please refer to Figure 1 , Figure 2 and Figure 4 , the electric motor 100 of the embodiments of the present application includes a housing 10, a stator assembly 40 and a rotor assembly 50. The housing 10 has an accommodation space 11 formed inside. The stator assembly 40 is arranged in the accommodation space 11 and includes an excitation member 42 and a magnetic member 41. The excitation member 42 includes an excitation frame 421 and a coil winding 422. The excitation frame 421 surrounds an excitation space 423. The excitation frame 421 includes a winding portion 421a and a limiting portion 421b connected to each other, and the coil winding 422 is wound around the winding portion 421a. The rotor assembly 50 is arranged in the excitation space 423 and includes a rotor core 52, which is magnetized under the excitation of the magnetic field generated by the excitation member 42 and generates a force with the magnetic member 41 to reciprocate in the excitation space 423. The limiting portion 421b is located in the excitation space 423, and the limiting portion 421b is used to limit the reciprocating rotation of the rotor core 52.

[0061] The housing 10 of the electric motor 100 is an element that provides a mounting carrier for the internal structure of the electric motor 100. The accommodation space 11 formed by the housing 10 provides a mounting space for the internal structure of the electric motor 100, such as the stator assembly 40 and the rotor assembly 50, which can be mounted in the accommodation space 11. In some embodiments, as shown in Figure 1 , the electric motor 100 can further include an end cover 20, which can cover the mounting port 12 on the housing 10. The mounting port 12 is an opening for the internal structure of the electric motor 100 to enter the housing 10. In this way, the housing 10 cooperates with the end cover 20 to enclose the accommodation space 11, providing a good operating environment for the internal structure of the electric motor 100.

[0062] In other embodiments, the electric motor 100 can not include the end cover 20, and the mounting port 12 on the housing 10 can cooperate with a structure outside the electric motor 100 to enclose the accommodation space 11, such as the electric toothbrush 1000 Figure 11In some embodiments, the housing of the electric toothbrush 1000 can be a closed housing, and the accommodating space 11 can be formed in the housing. In other embodiments, the accommodating space 11 can be open, for example, when the housing of the electric toothbrush 1000 is already a closed housing, even possibly with a waterproof design, so that the environment inside the housing of the electric toothbrush 1000 is already a good operating environment that is not disturbed by water or dust, and the accommodating space 11 can be open.

[0063] The stator assembly 40 is an assembly that is relatively fixed with the housing 10 and is used to drive the rotation of the rotor assembly 50. The excitation member 42 is a device for generating a changing magnetic field, which can be an electromagnet, for example. The magnetic member 41 is a device for generating a changing or constant magnetic field. When the magnetic member 41 is used to generate a changing magnetic field, the magnetic member 41 can be an electromagnet. When the magnetic member 41 is used to generate a constant magnetic field, the magnetic member 41 can be an electromagnet or a permanent magnet, which can be a rare earth permanent magnet, a metal alloy permanent magnet, a ferrite permanent magnet, or the like. The excitation frame 421 is a support frame for the coil winding 422 to be wound around. The excitation frame 421 can be made of a ferromagnetic medium, so that the excitation frame 421 can generate a stronger magnetic field under the excitation of the magnetic field generated by the coil winding 422, and can improve the magnetization degree of the rotor core 52. The excitation frame 421 can also be made of a common medium, such as plastic or aluminum alloy, etc. The coil winding 422 is a wire winding for generating a magnetic field. When a driving current is passed through the coil winding 422, the size and direction of the magnetic field generated by the excitation member 42 can be controlled, so as to control the rotor core 52.

[0064] The rotor assembly 50 is an assembly that can rotate under the control of the stator assembly 40 and output torque to the outside of the motor 100. The excitation space 423 formed around the excitation frame 421 is the space in which the excitation member 42 generates a changing magnetic field. The rotor core 52 is arranged in the excitation space 423, and thus can be magnetized by the magnetic field generated by the excitation member 42. Since the change of the magnetic field generated by the excitation member 42 is controlled by the driving current in the coil winding 422, the magnetization of the rotor core 52 (the orientation of the magnetic poles of the rotor core 52 and the strength of the magnetic field generated) is also controlled by the driving current. Therefore, the rotor core 52 can be made to perform a sweeping vibration by controlling the driving current.

[0065] Specifically, in one example, referring to Figure 3 and Figure 4 When the magnetization of the rotor core 52 changes, the force between the rotor core 52 and the four magnetic members 41 shown in the figure changes, so that the rotor core 52 performs a sweeping vibration. In another example, the magnetic member 41 can be provided with only two, as shown in Figure 4In the case shown, only two magnetic members 41 are provided at the upper left and upper right, or only two magnetic members 41 are provided at the left side, or only two magnetic members 41 are provided at the right side; in yet another example, only one magnetic member 41 can be provided, which extends in the sweeping direction of the rotor core 52 and has two magnetic poles with opposite polarities arranged in the sweeping direction of the rotor core 52. In the above examples, the magnetic member 41 can be acted on by the rotor core 52 by changing the magnetization of the rotor core 52, thereby driving the rotor core 52 to perform sweeping vibration.

[0066] The winding portion 421a of the excitation frame 421 is a portion for winding the coil winding 422, the winding portion 421a surrounds the excitation space 423, and the coil winding 422 is wound on the winding portion 421a and thus surrounds the excitation space 423. Thus, when the coil winding 422 is energized, an excitation magnetic field is generated in the excitation space 423, and the rotor core 52 is magnetized.

[0067] The limiting portion 421b is a portion of the excitation frame 421 that provides a limiting action for the rotor core 52. The rotor core 52 and the limiting portion 421b are both located in the excitation space 423, so the limiting portion 421b can limit the rotor core 52. In one example, as shown in Figure 4 When the rotor core 52 is rotated to a predetermined angle (for example, rotated clockwise to the limit position in Figure 4 ), the rotor core 52 can abut against the limiting portion 421b, thereby preventing the rotor core 52 from rotating beyond the predetermined range; in another example, the limiting portion 421b can be a pole shoe protruding towards the rotor core 52. In this example, the limiting portion 421b can be made of a ferromagnetic material, so that the limiting portion 421b can emit a high-intensity magnetic field. Since the rotor core 52 is magnetized due to the magnetic field generated by the excitation member 42, the magnetic field emitted by the limiting portion 421b tends to repel the rotor core 52. Thus, the limiting portion 421b can prevent the rotor core 52 from being too close to the limiting portion 421b, thereby limiting the rotor core 52.

[0068] It can be understood that when the limiting portion 421b abuts against the rotor core 52, the limiting portion 421b does not necessarily have to abut against the end portion 52c of the rotor core 52 in the excitation direction of the excitation member 42, but can abut against other portions of the rotor core 52, for example, the middle end portion 52c of the rotor core 52 in the excitation direction of the excitation member 42. The limiting portion 421b only needs to allow the rotor core 52 to rotate within a preset range and abut against the rotor core 52 when the rotor core 52 rotates to the limit position, so as to avoid further rotation of the rotor core 52. When the limiting portion 421b and the rotor core 52 repel each other through a magnetic field, the limiting portion 421b does not necessarily have to protrude towards the rotor core 52, but can also not protrude. However, the limiting portion 421b is made of ferromagnetic medium, so that a repulsive force sufficient to limit the rotor core 52 can be generated.

[0069] In summary, please refer to Figure 11 In the application embodiment, due to the arrangement of the limiting portion 421b, the rotor core 52 can be prevented from rotating beyond the preset range, and since the rotor core 52 is connected with the brush head 200 of the electric toothbrush 1000, the brush head 200 of the electric toothbrush 1000 can also be prevented from rotating beyond the preset range, so as to avoid the brush head 200 from rotating beyond the preset range to stimulate sensitive parts of the user's oral cavity, or even damage the oral tissue of the user. In addition, due to the limiting effect of the limiting portion 421b, the driving controller of the motor 100 can weaken the limiting control on the rotor core 52, so as to strengthen the motion control on the rotor core 52, that is, to make the rotor core 52 realize more accurate scanning vibration, thereby improving the accuracy of the motion control on the rotor core 52.

[0070] Please refer to Figure 3 , Figure 4 and Figure 5 In some embodiments, the rotor assembly 50 further includes a rotating shaft 51, and the rotor core 52 is sleeved on the rotating shaft 51 and includes two opposite end portions 52c distributed along the radial direction of the rotating shaft 51. From the direction of the rotating shaft 51 to the end portion 52c, the size of the excitation space 423 at the limiting portion 421b in the circumferential direction of the rotating shaft 51 increases.

[0071] The rotating shaft 51 is an output shaft of the rotor core 52, and the rotor core 52 drives the rotating shaft 51 to rotate, and the rotating shaft 51 outputs the rotation to the brush head 200 (as shown in Figure 11 At the same time, the rotating shaft 51 can also be a rotating shaft of the rotor core 52, that is, the rotor core 52 is fixedly connected with the rotating shaft 51, so as to be relatively rotatable with the stator assembly 40. Specifically, please refer to Figure 5The rotor assembly 50 is fixedly connected with the housing 10, the outer ring of the first bearing 71 is fixedly connected with the housing 10, the inner ring of the first bearing 71 is fixedly connected with the rotating shaft 51 (the inner ring is sleeved on the rotating shaft 51); the end cover 20 is fixedly connected with the housing 10, the outer ring of the second bearing 72 is fixedly connected with the end cover 20, the inner ring of the second bearing 72 is fixedly connected with the inner ring of the rotating shaft 51 (the inner ring is sleeved on the rotating shaft 51), and the rotor core 52 is located between the first bearing 71 and the second bearing 72 and is sleeved on the rotating shaft 51 and fixedly connected with the rotating shaft 51. Since the rotating shaft 51 and the stator assembly 40 are in a relative rotatable but non-translational relationship, the rotor core 52 can also be kept in a relative rotatable relationship with the stator assembly 40 through the rotating shaft 51.

[0072] Please refer to Figure 4 It can be seen that in the radial direction of the rotating shaft 51, the rotor core 52 has two opposite end portions 52c. Since the rotor core 52 rotates with the rotating shaft 51, the end portions 52c of the rotor core 52 sweep the largest path in a sweeping motion, and thus it can also be said that the end portions 52c of the rotor core 52 require the largest motion space in the same range of sweeping motion. In addition, the end portions 52c swing in the circumferential direction of the rotating shaft 51, so when the size of the energizing space 423 at the limiting portion 421b in the circumferential direction of the rotating shaft 51 is increased, more rotating space can be left for the end portions 52c of the rotor core 52, thereby improving the rotatable angle of the rotor core 52.

[0073] Please refer to Figure 4 In some embodiments, the rotor core 52 includes a core body 52a and a protruding portion 52b protruding from the core body 52a in the rotating direction of the rotor core 52. The protruding portion 52b is used to abut against the limiting portion 421b.

[0074] The protruding portion 52b protrudes from the core body 52a and is used to abut against the limiting portion 421b, so that the rotor core 52 can be limited only by the abutment of the protruding portion 52b and the limiting portion 421b. Therefore, in such embodiments, only a part (the protruding portion 52b) of the rotor core 52 abuts against the limiting portion 421b, avoiding the abutment of the entire rotor core 52 against the limiting portion 421b, which can reduce the abnormal sound generated when the rotor core 52 abuts against the limiting portion 421b. In addition, the protruding portion 52b can also generate a strong magnetic field to repel the limiting portion 421b, thereby reducing the probability of abutment between the protruding portion 52b and the limiting portion 421b and further reducing the abnormal sound.

[0075] Please refer to Figure 4In some embodiments, the protrusion 52b is arranged at the end 52c of the core body 52a. In this way, when the protrusion 52b abuts against the limiting portion 421b, the force applied by the limiting portion 421b to the protrusion 52b is greater in distance from the rotation shaft 51, so that the force applied by the limiting portion 421b to the protrusion 52b is greater in torque than the force of the rotation shaft 51. It can be understood that the force applied by the limiting portion 421b to the protrusion 52b is the force that hinders the rotation of the rotor core 52 out of the preset range, and thus the greater the force applied by the limiting portion 421b to the protrusion 52b in torque than the force of the rotation shaft 51, the better the effect of hindering the rotation of the rotor core 52. Therefore, when the protrusion 52b is arranged at the end 52c of the core body 52a, the relative force between the protrusion 52b and the limiting portion 421b is smaller in achieving the same effect of hindering the rotation of the rotor core 52, so that the protrusion 52b and the limiting portion 421b can be protected from damage, and the service life of the motor 100 is improved.

[0076] Please refer to Figure 4 , Figure 9 and Figure 10 In some embodiments, a limiting groove (not shown in the figure) is arranged on the limiting portion 421b, and when the rotor core 52 rotates in the excitation space 423, the protrusion 52b enters the limiting groove to cooperate with the limiting groove.

[0077] The limiting groove can be a groove recessed on the surface of the limiting portion 421b along the sweeping direction of the rotor core 52, and the limiting groove can match the surface of the protrusion 52b, so that the part of the protrusion 52b entering the limiting groove is in contact with the groove wall of the limiting groove; the limiting groove can also be in a stepped shape and can extend outward along the radial direction of the rotation shaft 51, and the protrusion 52b entering the limiting groove can abut against at least two mutually perpendicular stepped surfaces in the limiting groove at the same time. The limiting groove can also be arranged in multiple places, for example Figure 4 As shown in the figure, the rotor core 52 has four protrusions 52b, and four limiting grooves can be arranged corresponding to the four protrusions 52b, respectively. The arrangement of the limiting groove increases the contact area between the limiting portion 421b and the protrusion 52b, so that the impact force between the limiting portion 421b and the protrusion 52b can be dispersed to a larger contact surface, avoiding the damage of the limiting portion 421b or the protrusion 52b due to the excessive concentration of pressure on some places of the limiting portion 421b or the protrusion 52b.

[0078] Please refer to Figure 9In some embodiments, at least one of the convex portion 52b and the limiting portion 421b is provided with a buffer (not shown in the figure) for buffering the impact force between the convex portion 52b and the limiting portion 421b. The buffer can be made of a flexible material, such as silicone or rubber, or some textile fiber, such as nylon, chinlon or dacron. The buffer can be attached to the convex portion 52b and / or the limiting portion 421b, so that the convex portion 52b can indirectly abut against the limiting portion 421b through the buffer, i.e. the buffer separates the convex portion 52b and the limiting portion 421b. The limiting process between the rotor core 52 and the limiting portion 421b can be regarded as a collision process between the rotor core 52 and the limiting portion 421b. Since the buffer separates the convex portion 52b and the limiting portion 421b, the duration of the collision process can be increased, so that the impact force in the collision process can be reduced, and the rotor core 52 or the excitation frame 421 can be protected from damage.

[0079] Please refer to Figure 4 and Figure 8 In some embodiments, the rotor assembly 50 further comprises a rotating shaft 51, and the rotor core 52 is sleeved on the rotating shaft 51. The excitation member 42 comprises a first excitation member 42a and a second excitation member 42b. The first excitation member 42a and the second excitation member 42b are connected in the radial direction of the rotating shaft 51, and the first excitation member 42a and the second excitation member 42b jointly enclose an excitation space 423. In this way, the magnetic field strength in the excitation space 423 can be jointly determined by the magnetic field generated by the first excitation member 42a and the magnetic field generated by the second excitation member 42b. The currents in the coil windings 422 of the first excitation member 42a and the second excitation member 42b can be controlled separately, for example, the two coil windings 422 are controlled by two driving controllers respectively, so that the magnetic field strengths generated by the first excitation member 42a and the second excitation member 42b can be different. In this way, a magnetic field with a smaller span of strength variation can be obtained by combining the magnetic fields generated by the first excitation member 42a and the second excitation member 42b, so that the control accuracy of the movement of the rotor core 52 can be improved.

[0080] Of course, the currents in the coil windings 422 of the first excitation member 42a and the second excitation member 42b can be controlled jointly, for example, the coil windings 422 of the first excitation member 42a and the second excitation member 42b are connected in series, or the coil windings 422 of the first excitation member 42a and the second excitation member 42b are connected in parallel to the same driving controller.

[0081] Please refer to Figure 5 、 Figure 9 and Figure 10In some embodiments, the excitation member 42 comprises a connecting portion 421c. The connecting portion 421c of the first excitation member 42a is provided with a first coupling portion (not shown in the figure), and the connecting portion 421c of the second excitation member 42b is provided with a second coupling portion (not shown in the figure), the first coupling portion and the second coupling portion are matched to connect the first excitation member 42a and the second excitation member 42b.

[0082] The connecting portion 421c of the excitation member 42 is a part of the excitation member 42 for connecting with other excitation members 42. The connecting portion 421c can be a part of the excitation frame 421, i.e. Figure 10 As shown, the excitation frame 421 can comprise the winding portion 421a, the limiting portion 421b and the connecting portion 421c. The connecting portions 421c of the first magnetic member 41 and the second magnetic member 41 are oppositely arranged and can contact each other, so as to be coupled with each other.

[0083] The first coupling portion and the second coupling portion are structures on the first excitation member 42a and the second excitation member 42b for coupling with each other. Specifically, the first coupling portion can be a male buckle, and the second coupling portion can be a female buckle. The first coupling portion and the second coupling portion are matched by the buckle position to couple the first excitation member 42a and the second excitation member 42b. The arrangement of the first coupling portion and the second coupling portion makes the coupling of the first excitation member 42a and the second excitation member 42b more reliable, avoids the first excitation member 42a and the second excitation member 42b from being uncoupled or twisted due to the reaction force of the rotor core 52, and thus improves the reliability of the operation of the motor 100.

[0084] Please refer to Figure 5 , Figure 9 and Figure 10 In some embodiments, the first coupling portion (not shown in the figure) comprises at least two, two of the at least two first coupling portions are arranged at two opposite corners of the connecting portion 421c respectively, and the second coupling portion (not shown in the figure) is arranged in one-to-one correspondence with the first coupling portion. In these embodiments, the outer contour of the connecting portion 421c needs to approximately have opposite corners, for example Figure 5 As shown in the cross section, since the coupling portion surface is just in the cross section, the surface of the coupling portion is not cut, and it can be seen that in this example, the surface contour of the coupling portion is approximately rectangular. The opposite corners of a geometric figure are often the two corners farthest apart on the geometric figure, so that the arrangement of at least two of the first coupling portions at the opposite corners and the coupling with the second coupling portion can make the coupling positions of the first excitation member 42a and the second excitation member 42b as far apart as possible, which is better for avoiding the relative rotation (the rotation direction is along the surface of the coupling portion) of the first excitation member 42a and the second excitation member 42b.

[0085] Please refer to Figure 5 , Figure 9 and Figure 10In some embodiments, the first coupling part (not shown in the figure) can be of different types, for example, the first first coupling part is a groove, and the second first coupling part is a protrusion; and the second coupling part can be a protrusion or a groove corresponding to the first coupling part, that is, when the first first coupling part is a groove, and the second first coupling part is a protrusion, the second coupling part corresponding to the first first coupling part (not shown in the figure) is a protrusion, and the second coupling part corresponding to the second first coupling part is a groove. In this way, the first exciting member 42 can be provided with both grooves and protrusions, and it is not necessarily provided with only grooves or protrusions. The protrusion can enter the groove and cooperate with the groove, thereby connecting the first exciting member 42a and the second exciting member 42b. The structure for realizing the cooperation of the protrusion and the groove is simple, which can reduce the production cost of the exciting member 42, and in addition, it can also provide the effect of alignment when assembling the first exciting member 42a and the second exciting member 42b.

[0086] Please refer to Figure 8 and Figure 9 In some embodiments, the first exciting member 42a and the second exciting member 42b enclose a through hole 424, the rotor core 52 is fixedly connected with the rotating shaft 51, the rotating shaft 51 passes through the through hole 424 and rotates in the through hole 424.

[0087] The rotating shaft 51 can only pass through the through hole 424 without contacting the hole wall of the through hole 424, so that the stator assembly 40 is not subjected to the force of the rotating shaft 51, thereby ensuring the stability of the stator assembly 40. When the rotating shaft 51 does not contact the hole wall of the through hole 424, the rotating shaft 51 can be rotatably connected with the casing 10 by the first bearing 71 and the second bearing 72 as shown in Figure 5 The rotating shaft 51 and the hole wall of the through hole 424 can also be provided with a bearing, so that the hole wall of the through hole 424 can provide support for the rotating shaft 51, thereby improving the stability of the rotating shaft 51. The first exciting member 42a and the second exciting member 42b enclose the through hole 424, so that it is not necessary to punch holes on the exciting member 42 for the rotating shaft 51 to pass through, thereby facilitating the manufacturing of the exciting member 42 and reducing the manufacturing difficulty and cost.

[0088] Please refer to Figure 5 In some embodiments, the rotor assembly 50 further comprises a rotating shaft 51, and the rotor core 52 is sleeved on the rotating shaft 51. The exciting member 42 cooperates with the inner wall of the casing 10 in a direction perpendicular to the excitation direction in which the exciting member 42 generates a magnetic field and perpendicular to the extension direction of the rotating shaft 51. The casing 10 is often fixed by other structures outside the motor 100, for example, the outer shell of the electric toothbrush 1000 can fix the casing 10, so the casing 10 is often a stable carrier. When the exciting member 42 cooperates with the inner wall of the casing 10 in a direction perpendicular to the excitation direction in which the exciting member 42 generates a magnetic field and perpendicular to the extension direction of the rotating shaft 51, the stability of the exciting member 42 during operation can be improved. In addition, please refer toFigure 4 It can be seen that the direction of the reaction force of the rotor on the excitation member 42 is perpendicular to the extension direction of the rotor shaft 51 and the excitation direction, i.e. parallel to the direction in which the excitation member 42 cooperates with the inner wall of the housing 10. Therefore, the housing 10 can directly provide a fixing function for the excitation member 42 in this direction, and the stability of the excitation member 42 can be improved.

[0089] Please refer to Figure 2 In some embodiments, the housing 10 is provided with a mounting opening 12 for the stator assembly 40 and the rotor assembly 50 to enter the housing 10. The inner wall surface of the housing 10 that cooperates with the excitation member 42 is a cooperation surface 13, which is a flat surface and is connected to the mounting opening 12. In this way, when the excitation member 42 enters the housing 10, the cooperation surface 13 can provide a guiding function, and the excitation member 42 can slide along the cooperation surface 13 to reach the final installation position, which facilitates the installation of the excitation member 42. In addition, the flat cooperation surface 13 can also prevent the excitation member 42 from rotating in the opposite direction of the rotation direction of the rotor when the excitation member 42 is subjected to the reaction force of the rotor, thereby improving the stability of the excitation member 42.

[0090] Please refer to Figure 2 In some embodiments, the motor 100 further comprises a mounting member 60. The magnetic member 41 is mounted on the mounting member 60, and the mounting member 60 cooperates with the housing 10. In the excitation direction of the magnetic field generated by the excitation member 42, the excitation member 42 cooperates with the mounting member 60. Please refer to Figure 2 , Figure 7 and Figure 8 It can be seen that the mounting member 60 cooperates with the housing 10, which can prevent the mounting member 60 from rotating relative to the housing 10. Since the magnetic member 41 is mounted on the mounting member 60, the mounting member 60 will be subjected to the reaction force of the rotor core 52, thereby having a tendency to rotate in the opposite direction of the rotation of the rotor core 52. Through the mounting member 60, the magnetic member 41 can be stably fixed to the housing 10, thereby avoiding displacement of the magnetic member 41 and improving the reliability of the motor 100.

[0091] In the excitation direction of the excitation member 42, the excitation member 42 cooperates with the mounting member 60, which can limit the excitation member 42 in the excitation direction, thereby improving the stability of the excitation member 42. In particular, please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7It can be seen that the mounting member 60 is matched with the inner wall of the casing 10 at each position in the circumferential direction of the rotating shaft 51, thereby forming a stable connection with the casing 10; the magnetizing member 42 is matched with the matching surface 13, and also forms a stable connection with the casing 10; and the magnetizing member 42 is matched with the mounting member 60 in the magnetizing direction. It can be seen that the matching strength of the magnetizing member 42 with the mounting member 60 and the casing 10 can be mutually enhanced, thereby forming a stable whole and improving the stability of the motor 100 as a whole. It can be understood that the magnetizing direction refers to the direction of the magnetic field generated by the magnetizing member 42 in the magnetizing space 423, rather than the magnetic field generated by the magnetizing member 42 at other positions.

[0092] Please refer to Figure 2 In some embodiments, the mounting member 60 is provided with a clamping groove 61, and the magnetic member 41 is arranged in the clamping groove 61. Figure 2 In some embodiments, the magnetic member 41 is separated from the clamping groove 61. Figure 4 Figure 8 In some embodiments, the magnetic member 41 has been clamped in the clamping groove 61. It can be seen that the groove wall of the clamping groove 61 can provide a good limiting effect for the magnetic member 41, and at the same time, since the mounting member 60 is matched with the casing 10, the relative position between the magnetic member 41 and the casing 10 can be maintained stable. The stable relative position between the magnetic member 41 and the casing 10 can enable the magnetic member 41 to provide a stable attracting or repelling effect on the rotor core 52, thereby enabling the control of the rotor core 52 to be more accurate.

[0093] Please refer to Figure 9 In some embodiments, the rotor core 52 includes a plurality of sheet materials (not shown in the figure), and the plurality of sheet materials are laminated to form the rotor core 52. The sheet material is sheet-shaped, and thus can be laminated to form the rotor core 52. Since the resistance between the sheet materials is large (possibly due to the existence of contact resistance or the increase in resistance caused by the oxidation layer on the surface of the sheet material), the resistance of the rotor core 52 formed by lamination of the sheet materials is also large, so that the thermal efficiency of the eddy current field generated by the changing magnetic field in the magnetizing space 423 is greatly reduced, thereby reducing the eddy current loss of the rotor core 52. The lamination direction of the sheet material can be perpendicular to the magnetizing direction of the magnetizing member 42, and the sheet material can be a silicon steel sheet or a sheet material made of amorphous alloy.

[0094] The above-described embodiments only express several embodiments of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent scope. It should be noted that for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.​

Claims

1. An electric motor, characterized in that, include: A housing, wherein an accommodating space is formed inside the housing; A stator assembly is disposed within the accommodating space and includes an excitation element and a magnetic element; the excitation element includes an excitation frame and a coil winding; the excitation frame surrounds and forms an excitation space; the excitation frame includes a winding portion and a limiting portion connected to each other, and the coil winding is wound on the winding portion; and A rotor assembly is disposed in the excitation space and includes a rotor core, which is magnetized under the excitation of the magnetic field generated by the excitation element and interacts with the magnetic element to reciprocate within the excitation space. The limiting part is located within the excitation space and is used to limit the reciprocating rotation of the rotor core.

2. The motor according to claim 1, characterized in that, The rotor assembly further includes a shaft, on which the rotor core is fitted and includes two opposing ends, the two ends being radially distributed along the shaft, and the excitation space at the limiting portion increasing in circumferential direction along the shaft from the shaft to the ends.

3. The motor according to claim 1, characterized in that, The rotor core includes a core body and a protrusion. The protrusion protrudes from the core body along the rotation direction of the rotor core. The protrusion is used to abut against the limiting part.

4. The motor according to claim 3, characterized in that, The protrusion is located at the end of the iron core body.

5. The motor according to claim 3, characterized in that, The limiting part is provided with a limiting groove. When the rotor core rotates in the excitation space, the protrusion enters the limiting groove to cooperate with the limiting groove.

6. The motor according to claim 3, characterized in that, At least one of the protrusion and the limiting part is provided with a buffer member, which is used to buffer the impact force between the protrusion and the limiting part.

7. The motor according to claim 1, characterized in that, The rotor assembly further includes a rotating shaft, and the rotor core is sleeved on the rotating shaft; the excitation element includes a first excitation element and a second excitation element; the first excitation element and the second excitation element are connected radially on the rotating shaft, and the first excitation element and the second excitation element together form the excitation space.

8. The motor according to claim 7, characterized in that, The excitation component includes a connecting portion; the connecting portion of the first excitation component is provided with a first connecting portion, and the connecting portion of the second excitation component is provided with a second connecting portion, the first connecting portion and the second connecting portion cooperating to connect the first excitation component and the second excitation component.

9. The motor according to claim 8, characterized in that, The first joint includes at least two, and two of the first joints are respectively disposed at two opposite corners of the connecting portion. The second joint is disposed in a one-to-one correspondence with the first joint.

10. The motor according to claim 7, characterized in that, The first excitation element and the second excitation element form a through hole. The rotor core is fixedly connected to the rotating shaft. The rotating shaft passes through the through hole and rotates within the through hole.

11. The motor according to claim 1, characterized in that, The rotor assembly further includes a rotating shaft, and the rotor core is sleeved on the rotating shaft; in the direction perpendicular to the excitation direction in which the magnetic field is generated by the exciter and in the direction perpendicular to the extension direction of the rotating shaft, the exciter engages with the inner wall of the housing.

12. The motor according to claim 11, characterized in that, The housing is provided with an installation port for the stator assembly and the rotor assembly to enter the housing; the inner wall surface of the housing that mates with the excitation component is a mating surface, the mating surface is a plane, and the mating surface is connected to the installation port.

13. The motor according to claim 11, characterized in that, The motor also includes a mounting component; the magnetic component is mounted on the mounting component, the mounting component cooperates with the housing, and the excitation component cooperates with the mounting component in the excitation direction in which the excitation component generates the magnetic field.

14. The motor according to claim 13, characterized in that, The mounting component has a slot, and the magnetic component is disposed in the slot.

15. The motor according to any one of claims 1-14, characterized in that, The rotor core comprises a plurality of sheets, which are stacked to form the rotor core.

16. An electric toothbrush, characterized in that, include: The motor and brush head according to any one of claims 1-15, wherein the motor is connected to the brush head.

Images