Motor for electric toothbrush

Abstract

A motor for an electric toothbrush comprises a stator, a rotor and a shell, the stator and the rotor form an electronic assembly, and the motor assembly is installed in the shell. The stator comprises a silicon steel sheet, the cross section of the silicon steel sheet is U-shaped, and a coil is wound on the top plate; the rotor comprises a magnet mounting rack, a first magnet is arranged on one side of the magnet mounting rack, and a second magnet is arranged on the other side; one side, close to the stator, of the first magnet is a first magnetic pole, and one side, away from the stator, of the first magnet is a second magnetic pole; the side, close to the stator, of the second magnet is the first magnetic pole, and the side, away from the stator, is the second magnetic pole. The first magnetic pole of the first magnet and the first magnetic pole of the second magnet have the same polarity; a horizontal stable magnet located below the rotor is further arranged in the shell, the side, close to the rotor, of the horizontal stable magnet is a first magnetic pole, the side, away from the rotor, of the horizontal stable magnet is a second magnetic pole, and the polarity of the first magnetic pole of the horizontal stable magnet, the polarity of the second magnetic pole of the first magnet and the polarity of the second magnetic pole of the second magnet are the same.

Description

Technical Field

[0001] The utility model relates to a motor for an electric toothbrush. Background Art

[0002] "Magnetic levitation motors" (also known as "sonic wave motors") are widely used in electric toothbrushes. For example, Chinese utility model patent CN208272737U discloses such a magnetic levitation motor, which includes a stator and a rotor. The stator comprises silicon steel sheets and a coil. The rotor includes a magnet mounting assembly, on which magnets and a rotating shaft are mounted. The magnet mounting assembly and the silicon steel sheets are mounted on a fixture. The rotor is located within the silicon steel sheets, and the coil is wound around them. When the coil is energized, the silicon steel sheets are magnetized, generating a magnetic field force that acts on the magnets on the magnet mounting assembly, causing the magnet mounting assembly to rotate, which in turn drives the rotating shaft. By changing the direction of the current in the coil, the rotating shaft can be driven to rotate back and forth, causing the brush head of the electric toothbrush, which is mounted on the rotating shaft, to rotate back and forth.

[0003] However, during this process, a return spring must be installed at the lower end of the rotor to prevent the shaft from rotating 360° due to the electromagnetic force. Furthermore, after power is removed, the return spring must also return the brush head to a horizontal position. With frequent use, the return spring is prone to fatigue, resulting in a short service life and rapid failure, which can affect the performance of the electric toothbrush. Summary of the Invention

[0004] In order to overcome the above-mentioned deficiencies of the existing electric toothbrush motors, the present invention provides an electric toothbrush motor with a longer service life.

[0005] The utility model solves the technical problem with a technical solution as follows: a motor for an electric toothbrush, comprising a stator, a rotor, and a housing, wherein the stator and the rotor form a motor assembly, and the motor assembly is installed in the housing;

[0006] The stator includes silicon steel sheets, which include a first side plate, a second side plate, and a top plate connecting the first side plate and the second side plate, so that the cross section of the silicon steel sheet is U-shaped, and a rotor cavity is formed between the first side plate and the second side plate; a coil is wound on the top plate;

[0007] The rotor includes a magnet mounting frame, a rotating shaft is provided at the upper end of the magnet mounting frame, a first magnet corresponding to the first side plate is provided on one side of the magnet mounting frame, and a second magnet corresponding to the second side plate is provided on the other side of the magnet mounting frame, and the first magnet and the second magnet are both located in the rotor cavity and thus below the top plate;

[0008] The side of the first magnet close to the top plate is the first magnetic pole of the first magnet, and the side of the first magnet away from the top plate is the second magnetic pole of the first magnet; the side of the second magnet close to the top plate is the first magnetic pole of the second magnet, and the side of the second magnet away from the top plate is the second magnetic pole of the second magnet; the first magnetic pole of the first magnet and the first magnetic pole of the second magnet have the same polarity, and the second magnetic pole of the first magnet and the second magnetic pole of the second magnet have the same polarity;

[0009] The shell is also provided with a horizontal stabilizing magnet located below the rotor and corresponding to the rotor. The side of the horizontal stabilizing magnet close to the rotor is the first magnetic pole of the horizontal stabilizing magnet, and the side of the horizontal stabilizing magnet away from the rotor is the second magnetic pole of the horizontal stabilizing magnet. The polarity of the first magnetic pole of the horizontal stabilizing magnet, the polarity of the second magnetic pole of the first magnet, and the polarity of the second magnetic pole of the second magnet are the same.

[0010] The principle of rotor rotation in the present invention is essentially the same as that of the prior art, namely, when the coil is energized, the silicon steel sheets are magnetized. At this point, the first and second side plates of the silicon steel sheets are magnetized into two different magnetic poles. The magnetic field force of the silicon steel sheets acts on the first and second magnets on the magnet mounting assembly, thereby rotating the magnet mounting frame, which in turn drives the rotating shaft. By changing the direction of the current in the coil, the magnetic poles of the first and second side plates of the silicon steel sheets can be changed, thereby driving the magnet mounting frame to reciprocate. The principle of the rotor being able to reciprocate and avoid 360° rotation in the present invention is that when the magnet mounting frame rotates in one direction under the magnetic field force of the silicon steel sheets, the magnet on one side of the magnet mounting frame approaches the horizontal stabilizing magnet, that is, the second magnetic pole of the first magnet or the second magnetic pole of the second magnet approaches the first magnetic pole of the horizontal stabilizing magnet. Since the polarity of the first magnetic pole of the horizontal stabilizing magnet, the polarity of the second magnetic pole of the first magnet, and the polarity of the second magnetic pole of the second magnet are the same, based on the basic principle that like poles repel, the horizontal stabilizing magnet and the first magnet or the second magnet repel each other, thereby preventing further rotation of the magnet mounting frame. When the power is turned off, similarly, the horizontal stabilizing magnet repels the first magnet or the second magnet, so that the magnet mounting bracket returns to the horizontal position.

[0011] Furthermore, a magnetic conductive sheet is provided on one side of the magnet mounting frame close to the top plate.

[0012] Furthermore, the magnetic conductive sheet is in contact with the first magnet and the second magnet.

[0013] Furthermore, sockets are respectively provided at both ends of the magnet mounting frame, and slots are respectively provided on the sockets, and both ends of the first magnet and both ends of the second magnet are respectively inserted into the slots.

[0014] Furthermore, the two ends of the magnet mounting frame are respectively provided with sockets, the sockets are provided with slots, and the two ends of the magnetic conductive sheet are respectively inserted into the slots.

[0015] Furthermore, the shell is provided with an embedding groove, and the horizontal stabilizing magnet is embedded in the embedding groove.

[0016] Furthermore, an upper wire rack is provided at the upper end of the silicon steel sheet, and a lower wire rack is provided at the lower end of the silicon steel sheet, and the coil is wound on the upper wire rack and the lower wire rack.

[0017] Furthermore, an upper bearing is provided on the rotating shaft or on the upper end of the magnet mounting frame; and / or a lower bearing is provided on the lower end of the magnet mounting frame; and the upper bearing and the lower bearing are supported in the housing.

[0018] Furthermore, the housing includes a first housing and a second housing. The first housing and the second housing are matched to form the housing, and the motor assembly is sandwiched between the first housing and the second housing.

[0019] Furthermore, the horizontal stabilizing magnet is located between the first magnet and the second secondary magnet, and is at the same distance as the distance between the first magnet and the second secondary magnet.

[0020] The beneficial effect of the utility model is that the interaction between the horizontal stabilizing magnet and the first magnet and the second magnet prevents the rotor from rotating 360 degrees and helps the rotor to reset horizontally, and no return elastic sheet is used, which can greatly improve the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural diagram of the present utility model.

[0022] Figure 2 It is an exploded view of the present utility model.

[0023] Figure 3 It is a structural diagram of the motor assembly.

[0024] Figure 4 This is an exploded view of the motor assembly.

[0025] Figure 5 It is a schematic diagram of the rotor structure.

[0026] Figure 6 This is a schematic diagram of the rotor structure from another perspective.

[0027] Figure 7 This is an exploded view of the rotor.

[0028] Figure 8 It is a schematic diagram of the mutual coordination of the first magnet, the second magnet, the magnetic conductive sheet, and the horizontal stabilizing magnet.

[0029] Figure 9 This is a schematic diagram of the interaction among the first magnet, the second magnet, the magnetic conductive sheet, and the horizontal stabilizing magnet from another angle. DETAILED DESCRIPTION

[0030] The present invention will be described in further detail below with reference to the accompanying drawings and specific implementation methods.

[0031] Reference Figures 1-9 A motor for an electric toothbrush includes a stator 1, a rotor 2, and a housing. The stator 1 and the rotor 2 form a motor assembly, and the motor assembly is installed in the housing.

[0032] The stator 1 includes a silicon steel sheet 3, which includes a first side plate 3-1, a second side plate 3-2, and a top plate 3-3 connecting the first side plate 3-1 and the second side plate 3-2, so that the cross-section of the silicon steel sheet 3 is U-shaped, and a rotor cavity is formed between the first side plate 3-1 and the second side plate 3-1; a coil 4 is wound on the top plate 3-3.

[0033] The rotor 2 includes a magnet mounting frame 5, and the upper end of the magnet mounting frame 5 is provided with a rotating shaft 6 for connecting the brush head of the electric toothbrush. One side of the magnet mounting frame 5 is provided with a first magnet 7 corresponding to the first side plate 3-1, and the other side of the magnet mounting frame 5 is provided with a second magnet 8 corresponding to the second side plate 3-2. The first magnet 3-1 and the second magnet 3-1 are both located in the rotor cavity and thus below the top plate 3-3.

[0034] The side of the first magnet 7 close to the top plate 3-3 is the first magnetic pole of the first magnet 7 (the S pole in the figure), and the side of the first magnet 7 away from the top plate 3-3 is the second magnetic pole of the first magnet 7 (the N pole in the figure); the side of the second magnet 8 close to the top plate 3-3 is the first magnetic pole of the second magnet 8 (the S pole in the figure), and the side of the second magnet 8 away from the top plate 3-3 is the second magnetic pole of the second magnet 8 (the N pole in the figure); the first magnetic pole of the first magnet 7 and the first magnetic pole of the second magnet 8 have the same polarity (both are S poles in the figure)), and the second magnetic pole of the first magnet 7 and the second magnetic pole of the second magnet 8 have the same polarity (both are N poles in the figure).

[0035] The housing is also provided with a horizontal stabilizing magnet 9 located below and corresponding to the rotor 2. The side of the horizontal stabilizing magnet 9 closest to the rotor 2 is the first magnetic pole of the horizontal stabilizing magnet 9 (the N pole in the figure), and the side of the horizontal stabilizing magnet 9 farther from the rotor 2 is the second magnetic pole of the horizontal stabilizing magnet 9 (the S pole in the figure). The polarity of the first magnetic pole of the horizontal stabilizing magnet 9 (the N pole in the figure), the polarity of the second magnetic pole of the first magnet 7 (the N pole in the figure), and the polarity of the second magnetic pole of the second magnet 8 (the N pole in the figure) are the same. The horizontal stabilizing magnet 9 is generally required to be located between the first magnet 7 and the secondary magnet 8, and to be at an equal distance from the first magnet 7 and the secondary magnet 8.

[0036] The principle of rotor rotation in the present invention is basically the same as that in the prior art, that is, after the coil 4 is energized, the silicon steel sheet 3 is magnetized. At this time, the first side plate 3-1 and the second side plate 3-2 of the silicon steel sheet 3 are magnetized into two different magnetic poles. The magnetic field force of the silicon steel sheet 3 acts on the first magnet 7 and the second magnet 8 on the magnet mounting frame 5, thereby rotating the magnet mounting frame 5, and then driving the rotating shaft 6 to rotate. By changing the direction of the current in the coil 4, the polarity of the magnetic poles of the first side plate 3-1 and the second side plate 3-2 in the silicon steel sheet 3 can be changed, thereby driving the magnet mounting frame 5 to rotate back and forth. The principle by which the rotor 2 in the present invention can rotate back and forth without rotating 360° is as follows: when the magnet mounting frame 5 rotates in one direction under the magnetic field force of the silicon steel sheet 3, the magnet on one side of the magnet mounting frame 5 approaches the horizontal stabilizing magnet 9, that is, the second pole of the first magnet 7 or the second pole of the second magnet 8 approaches the first pole of the horizontal stabilizing magnet 9. Since the polarity of the first pole of the horizontal stabilizing magnet 9, the polarity of the second pole of the first magnet 7, and the polarity of the second pole of the second magnet 8 are the same, based on the basic principle that like poles repel, the horizontal stabilizing magnet 9 repels the first magnet 7 or the second magnet 8, thereby preventing the magnet mounting frame 5 from rotating further. When the power is cut off, the horizontal stabilizing magnet 9 similarly repels the first magnet 7 or the second magnet 8, causing the magnet mounting frame 5 to return to its horizontal position.

[0037] Based on the above principle, horizontal stabilizing magnets 9 of different magnetic strengths can be selected to control the rotation angle of the rotor 2, so as to produce electric toothbrushes suitable for different groups of people: when the magnetism of the horizontal stabilizing magnet 9 is strong, the first magnet 7 or the second magnet 8 rotates less and approaches the horizontal stabilizing magnet 9, and the repulsive force between the horizontal stabilizing magnet 9 and the first magnet 7 or the second magnet 8 can offset the magnetic field force of the silicon steel sheet 3, and the rotation angle of the rotating shaft 6 is small; when the magnetism of the horizontal stabilizing magnet 9 is weak, the first magnet 7 or the second magnet 8 rotates more and approaches the horizontal stabilizing magnet 9, and the repulsive force between the horizontal stabilizing magnet 9 and the first magnet 7 or the second magnet 8 can offset the magnetic field force of the silicon steel sheet 3, and the rotation angle of the rotating shaft 6 is large. However, the method of using a return elastic sheet in the existing technology is difficult to effectively adapt to the adjustment of the automatic rotation angle, especially it is difficult to enable the rotor to obtain a larger rotation angle.

[0038] In one embodiment, a magnetic sheet 10 is provided on a surface of the magnet mounting frame 5 near the top plate 3-3 for conducting magnetism. The sheet is typically made of iron and preferably contacts the first and second magnets 7 and 8. Under the action of the first and second magnets 7 and 8, the sheet 10 is magnetized, resulting in the sheet 10 having the same polarity (S pole in the figure) as the first and second poles of the first and second magnets 7. The provision of the sheet 10 facilitates magnetic conduction and enhances magnetic properties, ensuring smooth rotation of the rotor 2.

[0039] In one embodiment, the specific arrangement of the first magnet 7, the second magnet 8, and the magnetic conductive sheet 10 is as follows: sockets 11 are respectively provided at both ends of the magnet mounting frame 5, and slots 12 are provided on the sockets 11. The two ends of the first magnet 7, the two ends of the second magnet 8, and the two ends of the magnetic conductive sheet 10 are respectively inserted into the slots 12.

[0040] In one embodiment, the housing is provided with an embedding groove, and the horizontal stabilizing magnet 9 is embedded in the embedding groove, so that the horizontal stabilizing magnet 9 can be installed simply and stably.

[0041] In one embodiment, an upper wire rack 13 is provided at the upper end of the silicon steel sheet 3, and a lower wire rack 14 is provided at the lower end of the silicon steel sheet 3. The coil 4 is wound on the upper wire rack 13 and the lower wire rack 14 to prevent the coil 4 from being cut by the silicon steel sheet.

[0042] In one embodiment, an upper bearing 15 is provided on the rotating shaft 6 or at the upper end of the magnet mounting bracket 5; and / or a lower bearing 16 is provided at the lower end of the magnet mounting bracket 5. The upper bearing 15 and the lower bearing 16 are supported in the housing. The provision of the upper bearing 15 and / or the lower bearing 16 ensures smooth rotation of the rotor 2.

[0043] In one embodiment, the housing includes a first housing 17 and a second housing 18. The first housing 17 and the second housing 18 are matched to form the housing. The motor assembly is clamped between the first housing 17 and the second housing 18. At this time, the upper bearing 15 and the lower bearing 16 are also clamped between the first housing 17 and the second housing 18.

[0044] In one embodiment, a seal 19 is further provided on the rotating shaft 6 or the upper end of the magnet mounting frame 5 to seal the rotating shaft 6 from the housing or the magnet mounting frame 5 from the housing. The seal 19 can be in the form of a sealing sleeve or the like.

[0045] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0046] The above describes the implementation methods of the present invention. However, the present invention is not limited to the above implementation methods. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A motor for an electric toothbrush, comprising a stator, a rotor, and a housing, wherein the stator and the rotor form a motor assembly, and the motor assembly is mounted in the housing; The stator includes silicon steel sheets, which include a first side plate, a second side plate, and a top plate connecting the first side plate and the second side plate, so that the cross section of the silicon steel sheet is U-shaped, and a rotor cavity is formed between the first side plate and the second side plate; a coil is wound on the top plate; The rotor includes a magnet mounting frame, a rotating shaft is provided at the upper end of the magnet mounting frame, a first magnet corresponding to the first side plate is provided on one side of the magnet mounting frame, and a second magnet corresponding to the second side plate is provided on the other side of the magnet mounting frame, and the first magnet and the second magnet are both located in the rotor cavity and thus below the top plate; Its characteristics are: The side of the first magnet close to the top plate is the first magnetic pole of the first magnet, and the side of the first magnet away from the top plate is the second magnetic pole of the first magnet; the side of the second magnet close to the top plate is the first magnetic pole of the second magnet, and the side of the second magnet away from the top plate is the second magnetic pole of the second magnet; the first magnetic pole of the first magnet and the first magnetic pole of the second magnet have the same polarity, and the second magnetic pole of the first magnet and the second magnetic pole of the second magnet have the same polarity; The shell is also provided with a horizontal stabilizing magnet located below the rotor and corresponding to the rotor. The side of the horizontal stabilizing magnet close to the rotor is the first magnetic pole of the horizontal stabilizing magnet, and the side of the horizontal stabilizing magnet away from the rotor is the second magnetic pole of the horizontal stabilizing magnet. The polarity of the first magnetic pole of the horizontal stabilizing magnet, the polarity of the second magnetic pole of the first magnet, and the polarity of the second magnetic pole of the second magnet are the same.

2. The electric toothbrush motor according to claim 1, wherein: A magnetic conductive sheet is further provided on one side of the magnet mounting frame close to the top plate.

3. The electric toothbrush motor according to claim 2, wherein: The magnetic conductive sheet is in contact with the first magnet and the second magnet.

4. The electric toothbrush motor according to claim 1, wherein: Sockets are respectively provided at both ends of the magnet mounting frame, and slots are respectively provided on the sockets. Both ends of the first magnet and both ends of the second magnet are inserted into the slots.

5. The electric toothbrush motor according to claim 2, wherein: Sockets are respectively provided at both ends of the magnet mounting frame, slots are respectively provided on the sockets, and both ends of the magnetic conductive sheet are respectively inserted into the slots.

6. The electric toothbrush motor according to any one of claims 1 to 5, characterized in that: The shell is provided with an embedding groove, and the horizontal stabilizing magnet is embedded in the embedding groove.

7. The electric toothbrush motor according to any one of claims 1 to 5, characterized in that: An upper wire rack is provided at the upper end of the silicon steel sheet, and a lower wire rack is provided at the lower end of the silicon steel sheet. The coil is wound on the upper wire rack and the lower wire rack.

8. The electric toothbrush motor according to any one of claims 1 to 5, characterized in that: An upper bearing is provided on the rotating shaft or the upper end of the magnet mounting frame; and / or a lower bearing is provided on the lower end of the magnet mounting frame; The upper bearing and the lower bearing are supported in the housing.

9. The electric toothbrush motor according to any one of claims 1 to 5, characterized in that: The housing comprises a first housing and a second housing. The first housing and the second housing are matched to form the housing. The motor assembly is sandwiched between the first housing and the second housing.

10. The electric toothbrush motor according to any one of claims 1 to 5, characterized in that: The horizontal stabilizing magnet is located between the first magnet and the second secondary magnet, and is at the same distance from the first magnet and the second secondary magnet.

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