Micro servo motor for electric toothbrush

Abstract

The utility model discloses a micro servo motor for an electric toothbrush, which belongs to the technical field of micro servo motors and comprises a casing, a stator component connected to the inner wall of the casing, a front end bearing connected to the front end of the casing, a rear cover connected to the rear end of the casing, and a rear end bearing connected to the inside of the rear cover. The rotor assembly is installed inside the casing through a front end bearing and a rear end bearing, the rotor assembly comprises a shaft, the circumference of the shaft is connected with a rotor iron core, four symmetrically arranged magnetic shoes are embedded in the rotor iron core, the tail end of the rotor iron core is connected with an elastic sheet, the other end of the elastic sheet is connected with a rear cover, and the inner side of the rear cover is connected with an FPC. According to the utility model, the rotor assembly and the rear cover are connected through the elastic sheet of the metal component, 360-degree rotation of the rotor assembly is prevented through the elastic sheet, and compared with a spring welded on the shaft and the rear cover, the structure is simpler, and the cost is lower.

Description

Technical Field

[0001] The utility model belongs to the technical field of micro servo motors, and in particular relates to a micro servo motor for an electric toothbrush. Background Art

[0002] Currently, there are two types of motors for electric toothbrushes on the market. One is a simple sonic motor, which is derived from an ordinary iron core motor and has the characteristics of being simple in structure and principle. However, due to the small number of coils (only 2), the force on the magnet is small, so it is accompanied by some disadvantages, including: (1) small swing amplitude, usually only ±10° at most; (2) small torque; (3) poor controllability and a single experience.

[0003] The other is a micro servo motor with 6 coils and a Hall FPC board. The FPC board feeds back the rotation angle information to the toothbrush control board, which can accurately control the speed and swing amplitude. At the same time, in order to prevent the rotor from rotating 360 degrees when the power is off, a spiral spring is added to the rotor shaft. Although it plays a role, there is a problem of complex structure, and the casing and back cover are both metal die-castings, which are costly.

[0004] Therefore, there is an urgent need for a micro servo motor with good reliability, simple structure and low cost. Utility Model Content

[0005] In order to solve the problems raised in the above background technology, the utility model provides a micro servo motor for an electric toothbrush, which has the characteristics of good reliability, simple structure and low cost.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a micro servo motor for an electric toothbrush, comprising a casing, a stator assembly connected to the inner wall of the casing, a front end bearing connected to the front end of the casing, a rear end of the casing connected to the rear cover, the interior of the rear cover connected to the rear end bearing, a rotor assembly installed inside the casing through the front end bearing and the rear end bearing, the rotor assembly comprising a shaft, a rotor core connected to the circumference of the shaft, four symmetrically arranged magnetic tiles embedded in the rotor core, a spring connected to the tail end of the rotor core, the other end of the spring connected to the rear cover, and an FPC connected to the inner side of the rear cover.

[0007] In order to provide feedback information of the rotation angle to the toothbrush control board, further, the FPC is an FPC with a Hall sensor.

[0008] In order to generate a magnetic field by energizing, the stator assembly further includes a stator core, and insulating frames are inserted into both ends of the stator core, and a coil is wound around the insulating frame.

[0009] In order to provide an escape space for the FPC and also to position the installation of the FPC, a notch groove is further provided on the back cover.

[0010] In order to install the spring piece, further, a slot is provided at the tail of the shaft and a slot is provided on the rear cover.

[0011] In order to ensure that the rotor assembly does not deflect radially during rotation, further, the connection portion between the shaft and the spring sheet is located inside the rear end bearing.

[0012] In order to realize the riveting connection between the casing and the back cover, further, the casing is a stretch molding structure, the back cover is an injection molding structure, and a plurality of riveting grooves are provided on the back cover.

[0013] In order to position the motor as a whole and prevent the body from rotating, further, a rectangular block is integrally formed on the outer side of the rear cover, and the slot is arranged inside the rectangular block.

[0014] Compared with the prior art, the beneficial effects of the utility model are:

[0015] 1. The utility model connects the rotor assembly and the rear cover through a metal spring piece, and prevents the rotor assembly from rotating 360 degrees through the spring piece. Compared with the spring welded on the shaft and the rear cover, the structure is simpler and the cost is lower;

[0016] 2. The utility model has a notch groove on the rear cover to provide a space for the FPC to avoid and also to position the installation of the FPC;

[0017] 3. The connection part between the shaft and the spring piece of the utility model is located inside the rear end bearing, and the double bearing plus spring piece structure is adopted, which not only ensures that the rotor assembly will not deflect radially during rotation, but also can achieve the purpose of preventing the rotor assembly from rotating 360 degrees;

[0018] 4. The housing of the utility model is a stretch-molded structure, and the back cover is an injection-molded structure. The back cover is provided with a plurality of riveting grooves. The housing and the back cover are connected by riveting, which has better stability than bonding by glue.

[0019] 5. The outer side of the rear cover of the utility model is integrally formed with a rectangular block, through which the motor is positioned as a whole to prevent the body from rotating. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0021] Figure 1 It is a schematic diagram of the explosion of the structure of the utility model;

[0022] Figure 2 It is a structural schematic diagram of the stator assembly of the utility model;

[0023] Figure 3 It is a structural schematic diagram of the rotor assembly of the utility model;

[0024] Figure 4 It is a cross-sectional structural schematic diagram of the utility model;

[0025] Figure 5 and 6 They are all structural schematic diagrams of the rear cover of the utility model;

[0026] Figure 7 This is a schematic diagram of the structure of the FPC connected to the back cover of the utility model;

[0027] In the figure: 1, front end bearing; 2, housing; 3, stator assembly; 31, stator core; 32, coil; 33, insulation frame; 4, rotor assembly; 41, shaft; 42, rotor core; 43, spring piece; 44, slot; 45, magnetic tile; 5, FPC; 6, back cover; 61, slot; 62, notch slot; 63, rivet slot; 64, rectangular block; 7, rear end bearing. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] Example 1

[0030] See also Figure 1-7 The utility model provides the following technical solutions: a micro servo motor for an electric toothbrush, comprising a casing 2, a stator assembly 3 connected to the inner wall of the casing 2, a front end bearing 1 connected to the front end of the casing 2, a rear end of the casing 2 connected to the rear cover 6, a rear end bearing 7 connected to the interior of the rear cover 6, a rotor assembly 4 installed inside the casing 2 through the front end bearing 1 and the rear end bearing 7, the rotor assembly 4 comprising a shaft 41, a rotor core 42 connected to the circumference of the shaft 41, four symmetrically arranged magnetic tiles 45 embedded in the rotor core 42, a spring 43 connected to the tail end of the rotor core 42, the spring 43 is a metal component, the other end of the spring 43 is connected to the rear cover 6, and the inner side of the rear cover 6 is connected to the FPC5.

[0031] By adopting the above technical solution, the utility model connects the rotor assembly 4 and the rear cover 6 through the spring sheet 43 of the metal component, and prevents the rotor assembly 4 from rotating 360 degrees through the spring sheet 43. Compared with the spring welded on the shaft and the rear cover, the structure is simpler and the cost is lower.

[0032] Specifically, FPC5 is an FPC with a Hall sensor, and a circuit on FPC5 is composed of two Hall devices and four capacitors.

[0033] By adopting the above technical solution, feedback information of the rotation angle is provided to the toothbrush control panel.

[0034] Specifically, the stator assembly 3 includes a stator core 31 , and insulating frames 33 are inserted into both ends of the stator core 31 , and the coil 32 is wound around the insulating frame 33 .

[0035] The above technical solution is used to generate a magnetic field by applying electricity.

[0036] Specifically, a notch groove 62 is provided on the rear cover 6 .

[0037] By adopting the above technical solution, an avoidance space is provided for FPC5, and the installation of FPC5 can also be positioned.

[0038] Specifically, a clamping slot 44 is provided at the tail of the shaft 41 , and a slot 61 is provided on the rear cover 6 .

[0039] The above technical solution is used to install the spring piece 43.

[0040] Specifically, the connection portion between the shaft 41 and the spring sheet 43 is located inside the rear end bearing 7 .

[0041] By adopting the above technical solution and the structure of double bearings plus spring pieces 43, it is ensured that the rotor assembly 4 will not deflect radially during rotation, and the purpose of preventing the rotor assembly from rotating 360 degrees can be achieved.

[0042] Example 2

[0043] The present embodiment is different from the first embodiment in that: specifically, the housing 2 is a stretch-molded structure, the rear cover 6 is an injection-molded structure, and the rear cover 6 is provided with a plurality of riveting grooves 63 .

[0044] By adopting the above technical solution, the housing 2 and the back cover 6 are connected by riveting, which has better stability than bonding by glue.

[0045] Example 3

[0046] The present embodiment is different from the first embodiment in that: specifically, a rectangular block 64 is integrally formed on the outer side of the rear cover 6 , and the slot 61 is arranged inside the rectangular block 64 .

[0047] By adopting the above technical solution, the entire motor is positioned through the rectangular block 64 to prevent the body from rotating.

[0048] In summary, the utility model connects the rotor assembly 4 and the back cover 6 through the spring sheet 43 of the metal component, and prevents the rotor assembly 4 from rotating 360 degrees by the spring sheet 43. Compared with the spring welded on the shaft and the back cover, the structure is simpler and the cost is lower; the back cover 6 of the utility model is provided with a notch groove 62 to provide an escape space for the FPC5, and at the same time, the installation of the FPC5 can be positioned; the connection part between the shaft 41 and the spring sheet 43 of the utility model is located inside the rear end bearing 7, and the structure of double bearings plus spring sheets 43 is adopted, which not only ensures that the rotor assembly 4 will not deflect radially during the rotation process, but also can achieve the purpose of preventing the rotor assembly from rotating 360 degrees; the housing 2 of the utility model is a stretch molding structure, and the back cover 6 is an injection molding structure. A plurality of rivet grooves 63 are provided on the back cover 6. The housing 2 and the back cover 6 are connected by riveting, which has better stability than bonding by glue; the outer side of the back cover 6 of the utility model is integrally formed with a rectangular block 64, and the motor is positioned as a whole by the rectangular block 64 to prevent the body from rotating.

[0049] Finally, it should be noted that the above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A micro servo motor for an electric toothbrush, comprising a housing, characterized in that: The inner wall of the casing is connected to a stator assembly, the front end of the casing is connected to a front end bearing, the rear end of the casing is connected to a rear cover, the interior of the rear cover is connected to a rear end bearing, the rotor assembly is installed inside the casing through the front end bearing and the rear end bearing, the rotor assembly includes a shaft, the circumference of the shaft is connected to a rotor core, four symmetrically arranged magnetic tiles are embedded in the rotor core, the tail end of the rotor core is connected to a spring, the other end of the spring is connected to the rear cover, and the inner side of the rear cover is connected to an FPC.

2. A micro servo motor for an electric toothbrush according to claim 1, characterized in that: The FPC is an FPC with a Hall sensor.

3. A micro servo motor for an electric toothbrush according to claim 1, characterized in that: The stator assembly comprises a stator core, both ends of which are inserted with insulating frames, and a coil is wound around the insulating frame.

4. The micro servo motor for an electric toothbrush according to claim 1, characterized in that: The back cover is provided with a notch groove.

5. The micro servo motor for an electric toothbrush according to claim 1, characterized in that: The tail of the shaft is provided with a card slot, and the rear cover is provided with a slot.

6. The micro servo motor for an electric toothbrush according to claim 1, characterized in that: The connecting portion between the shaft and the spring sheet is located inside the rear end bearing.

7. The micro servo motor for an electric toothbrush according to claim 1, characterized in that: The casing is a stretch-molded structure, the back cover is an injection-molded structure, and a plurality of riveting grooves are arranged on the back cover.

8. The micro servo motor for an electric toothbrush according to claim 1, characterized in that: A rectangular block is integrally formed on the outer side of the rear cover, and the slot is arranged inside the rectangular block.

Images