CN211930366U

CN211930366U - Small-sized motor device for preventing coil from scattering

Info

Publication number: CN211930366U
Application number: CN202020635447.7U
Authority: CN
Inventors: 朱忠磊
Original assignee: Ray Vince Shenzhen Technology Co ltd
Current assignee: Ray Vince Shenzhen Technology Co ltd
Priority date: 2020-04-24
Filing date: 2020-04-24
Publication date: 2020-11-13
Anticipated expiration: 2030-04-24

Abstract

The utility model provides a prevent small-size motor device that coil scatters, it includes the center pin, the cover is located the epaxial rotor of center, locate the magnet group on the rotor, locate the outer stator of rotor, locate first coil and second coil between rotor and the stator, a serial communication port, be equipped with the backing sheet between first coil and second coil, the one end and the first coil butt of backing sheet, the other end and the second coil butt of backing sheet, the backing sheet supports first coil and second coil and supports tightly on the stator. The utility model discloses a first coil and second coil overlap respectively and locate on the stator, are equipped with the backing sheet between first coil and second coil, and the backing sheet can prop tight first coil and second coil, and the tip cartridge of first coil and second coil is in the end cover, and it can be lived by the end cover constraint, consequently, first coil and second coil just are difficult to scatter to can improve the stability of performance and the security of product.

Description

Small-sized motor device for preventing coil from scattering

[ technical field ] A method for producing a semiconductor device

The utility model relates to a motor, in particular to prevent small-size motor device that coil scatters.

[ background of the invention ]

The small high-frequency vibration motor is widely applied to various places in life, such as household products of electric toothbrushes, facial cleaning instruments and the like. The small-sized vibration motor has a small shape and a relatively high frequency of reciprocating rotation. For such motors, it usually includes a stator, a rotor, a central shaft and a coil, and for motors with different structures, the internal structure of the motor is different. In general, when designing the structure of such a motor, it is necessary to consider the problems of performance stability, miniaturization, easy processing and assembly, and the like. In the prior art, the coil is usually directly sleeved on the stator or the rotor, and during the motor process, especially during high-frequency vibration, wires of the coil may be scattered, and the scattering of the coil may affect the normal rotation of the rotor, so that a fault or a safety problem may occur during the working process.

[ Utility model ] content

The present invention is directed to solve the above problems, and provides a small-sized motor device for preventing a coil from scattering.

In order to solve the problem, the utility model provides a prevent small-size motor device that coil scatters, it includes center pin, cover locate epaxial rotor in center, locate magnet group on the rotor, locate the outer stator of rotor, locate first coil and second coil between rotor and the stator, a serial communication port be equipped with the backing sheet between first coil and the second coil, the one end of backing sheet with first coil butt, the other end of backing sheet with second coil butt, the backing sheet will first coil and second coil support tightly on the stator.

The support pieces comprise a first support piece and a second support piece, the first support piece and the second support piece are arranged at intervals and are respectively abutted between the edges of the two ends of the first coil and the second coil.

Furthermore, two ends of the first supporting piece are respectively provided with a first abutting inclined surface, two ends of the second supporting piece are respectively provided with a second abutting inclined surface, and the first abutting inclined surface and the second abutting inclined surface are arranged in opposite directions and face to two end edges of the first coil and the second coil.

Furthermore, the stator is formed by laminating silicon steel sheets, the whole stator is cylindrical, a first pole shoe and a second pole shoe are symmetrically arranged on the inner wall of the stator, the first pole shoe and the second pole shoe are oppositely spaced, the first coil is sleeved on the first pole shoe, and the second coil is sleeved on the second pole shoe.

Furthermore, a shell is sleeved outside the stator, one end of the central shaft extends out of the shell, the other end of the shell, opposite to the extending end of the central shaft, is connected with an end cover in an involutory mode, an elastic sheet is arranged between the end cover and the central shaft, one end of the elastic sheet is fixedly connected with the central shaft, and the other end of the elastic sheet is fixedly connected with the end cover.

Furthermore, a first positioning groove and a second positioning groove are formed in one end, facing the shell, of the end cover, the first positioning groove is opposite to the first coil, the second positioning groove is opposite to the second coil, the end portion of the first coil is inserted into the first positioning groove, and the end portion of the second coil is inserted into the second positioning groove.

Furthermore, the first coil is in a ring shape, the center of the first coil is provided with a first positioning hole matched with the first pole shoe in shape, and the first pole shoe is positioned in the first positioning hole; the second coil is in a ring shape, a second positioning hole matched with the second pole shoe in shape is formed in the center of the second coil, and the second pole shoe is located in the second positioning hole.

Furthermore, two ends of the stator opening are respectively provided with an insulating piece, one end of each insulating piece is respectively lapped on two ends of the stator, and the other end of each insulating piece covers the end parts of the first pole shoe and the second pole shoe, so that the first pole shoe and the second pole shoe are respectively isolated from the first coil and the second coil.

Furthermore, a central shaft hole is formed in the center of the rotor, and the central shaft is sleeved in the central shaft hole and can synchronously rotate along with the rotor; a plurality of strip-shaped magnet grooves which are mutually spaced are symmetrically distributed on the outer wall of the rotor, and the magnet groups are arranged in the magnet grooves.

Further, the magnet slots are parallel to the central shaft, symmetrically distributed outside two sides of the first pole shoe and the second pole shoe and respectively face the first coil and the second coil.

The beneficial contributions of the utility model reside in that, it has effectively solved above-mentioned problem. The utility model discloses a first coil and second coil overlap respectively and locate on the stator, are equipped with the backing sheet between first coil and second coil, and the backing sheet can prop tight first coil and second coil, and the tip cartridge of first coil and second coil is in the end cover, and it can be lived by the end cover constraint, consequently, first coil and second coil just are difficult to scatter to can improve the stability of performance and the security of product. The utility model discloses a prevent small-size motor device that coil scatters has simple structure, the high characteristics of security, and it has very strong practicality, should widely popularize.

[ description of the drawings ]

Fig. 1 is a schematic view of the overall structure of the present invention.

Fig. 2 is an exploded view of the overall structure of the present invention.

Fig. 3 is an exploded view of the present invention.

Fig. 4 is a sectional view.

Fig. 5 is a sectional view in another direction.

The attached drawings are as follows: the stator comprises a central shaft 10, an extending end 11, a magnet slot 12, a stator 20, a first pole shoe 21, a second pole shoe 22, a flat plate portion 23, an arc plate portion 24, a rotor 30, a central shaft hole 31, a magnet slot 32, a magnet group 40, a first coil 51, a first positioning hole 511, a second coil 52, a second positioning hole 521, an insulating member 60, a main body portion 61, a flange portion 62, a positioning groove portion 63, a plate portion 631, an opening 64, a support sheet 70, a first support sheet 71, a first abutting inclined surface 711, a second support sheet 72, a second abutting inclined surface 721, a shell 80, a bearing hole 81, a bearing 82, an end cover 90, a first positioning groove 91, a second positioning groove 92 and a spring sheet 100.

[ detailed description ] embodiments

The following examples are further to explain and supplement the present invention, and do not constitute any limitation to the present invention.

As shown in fig. 1 to 5, the main point of the small motor device for preventing the coil from scattering of the present invention is that the coil arranged on the stator 20 can be restrained by the multiple structure to prevent the coil from scattering, and further, the stability and safety of the product can be improved.

As shown in fig. 1 to 5, the small-sized motor device for preventing the coil from being scattered according to the present invention includes a central shaft 10, a stator 20, a rotor 30, a magnet assembly 40, a first coil 51, a second coil 52, a support sheet 70, a housing 80, an end cover 90, and a spring sheet 100.

As shown in fig. 1 to 5, the rotor 30 is made of a magnetic material, and in the present embodiment, is formed by laminating a plurality of silicon steel sheets. The rotor 30 has an axisymmetrical structure, a central shaft hole 31 extending along the length direction of the rotor 30 is formed in the center of the rotor 30, and the central axis of the central shaft hole 31 coincides with the symmetry axis of the rotor 30. The central shaft hole 31 is a through hole. To facilitate the installation of the magnet assembly 40, parallel spaced magnet slots 32 are provided in the outer wall of the rotor 30. The magnet slots 32 are strip-shaped and symmetrically distributed, and are parallel to the central axis 10. In this embodiment, four elongated magnet slots 32 are disposed on the outer wall of the rotor 30, and are respectively spaced in parallel and symmetrically distributed as a whole. In this embodiment, the magnet slot 32 penetrates from one end of the rotor 30 to the other end thereof.

As shown in fig. 1 to 5, the magnet assembly 40 includes 4 elongated magnets, the shape of which matches the shape of the magnet slot 32, and which can be embedded in the magnet slot 32. The magnetic poles of the magnet set 40 are arranged according to the prior art.

As shown in fig. 1 to 5, the central shaft 10 is installed in a central shaft hole 31 of the rotor 30 and can rotate synchronously with the rotor 30. The central shaft 10 and the central shaft hole 31 can be synchronously rotated by a known assembly method or an assembly structure. The length of the central shaft 10 is greater than the length of the rotor 30. One end of the central shaft 10 extends out of the rotor 30 to form an extended end 11, which is used for connecting with other objects to be driven, such as a toothbrush head, to drive the toothbrush head to vibrate back and forth.

As shown in fig. 1 to 5, the stator 20 is disposed outside the rotor 30 and inside the housing 80. The stator 20 is made of a magnetic material, and in the present embodiment, is formed by laminating a plurality of silicon steel sheets. The stator 20 is formed in a cylindrical shape with openings 64 at both ends. A first pole piece 21 and a second pole piece 22 extending along the axial direction of the stator 20 are symmetrically arranged on the inner wall of the stator. The first pole piece 21 can be used for positioning and installing the first coil 51, and the second pole piece 22 can be used for positioning and installing the second coil 52. The stator 20 has a cylindrical shape to facilitate the rotation of the rotor 30 therein, and in this embodiment, the cross section of the stator has a racetrack shape, and the racetrack shape includes parallel and spaced flat plate portions 63123 and arc plate portions 63124 connecting the same side edges of the two flat plate portions 63123. The lengths of the flat plate portion 63123 and the arc plate portion 63124 preferably correspond to the length of the rotor 30. The first pole piece 21 and the second pole piece 22 are provided at the center of the inner side surface of the arc plate portion 63124. The first and

second pole pieces

21 and 22 may be used for magnetic gathering, which may concentrate magnetism to enhance magnetic force action. The first pole piece 21 and the second pole piece 22 are long, extend along the length direction of the stator 20, and are spaced apart from and parallel to the flat plate portion 63123. In this embodiment, the lengths of the first pole piece 21, the second pole piece 22 and the flat plate portion 63123 are the same.

As shown in fig. 1 to 5, in order to insulate and isolate the first coil 51, the second coil 52 and the stator 20, an insulating member 60 is respectively disposed at two open ends of the stator 20. The insulating member 60 is sleeved at two ends of the stator 20, specifically, one end of the insulating member 60 is lapped on an end of the insulating member 60, and the other end of the insulating member 60 covers the ends of the first pole piece 21 and the second pole piece 22, so as to cover two ends of the stator 20, so that when the first coil 51 and the second coil 52 are sleeved on the first pole piece 21 and the second pole piece 22, the first coil 51 and the second coil 52 do not contact with the stator 20, and the first coil 51 and the second coil 52 are isolated from the stator 20.

In this embodiment, as shown in fig. 1 to 5, the insulating member 60 includes a cylindrical main body portion 61, a protruding portion 62 extending outward and having an annular shape is provided at one end of the main body portion 61, and positioning groove portions 63 are symmetrically provided on an inner wall of the main body portion 61. The main body portion 61 has a shape matching the shape of the stator 20, and an outer dimension thereof is smaller than or equal to an inner dimension of the stator 20, so that the main body portion 61 can be fitted inside the stator 20. Preferably, when the main body 61 is sleeved in the stator 20, the outer wall of the main body 61 is attached to the inner wall of the stator 20. The protruding edge part 62 is formed by extending outward from the end of the main body part 61, and has a size matching the size of the end face of the stator 20, and can overlap the end face of the stator 20. The positioning slot 63 is used to fit over the first pole piece 21 and the second pole piece 22, and includes parallel spaced plate portions 631, and the distance between the plate portions 631 is not less than the thickness of the first pole piece 21 and the second pole piece 22. The plate portion 631 extends from one end of the main body portion 61 to the other end thereof in the axial direction thereof. In this embodiment, the ends of the plate portion 631 facing the first and

second pole pieces

21 and 22 are connected together by a connection portion, which can more conveniently enclose the first and

second coils

51 and 52 for insulation and isolation. The other end of the plate portion 631 opposite to the connecting portion is shaped as an opening 64, which facilitates the sleeving of the positioning slot 63 on the first pole piece 21 and the second pole piece 22. In order to facilitate the fitting of the entire insulator 60 to the stator 20, the main body portion 61 is provided with openings 64 that communicate with the space between the plate portions 631. The insulating member 60 is lapped on the end portion of the stator 20, the protruding edge portion 62 is lapped on the end surface of the stator 20, the main body portion 61 is located in the end portion of the stator 20 and attached to the inner wall of the stator 20, and the positioning groove portion 63 is sleeved outside the first pole piece 21 and the second pole piece 22.

As shown in fig. 1 to 5, a first coil 51 and a second coil 52 are provided between the stator 20 and the rotor 30 in order to allow the stator 20 and the rotor 30 to interact with each other. The first coil 51 and the second coil 52 have the same shape and structure, are overall in a long coil shape, and are respectively provided at the center thereof with a first positioning hole 511 and a second positioning hole 521, which are matched with the first pole piece 21 and the second pole piece 22 in shape. The first positioning hole 511 has a size slightly larger than the outer peripheral size of the first pole piece 21, so that the first coil 51 can be sleeved on the first pole piece 21. The second positioning hole 521 has a size slightly larger than the outer dimension of the second pole piece 22, so that the second coil 52 can be sleeved on the second pole piece 22. The overall shape of the first coil 51 and the second coil 52 should match the shape of the arc plate 63124 of the stator 20, which is also arc-shaped.

As shown in fig. 1 to 5, a support piece 70 is provided between the first coil 51 and the second coil 52 to tightly hold the first coil 51 and the second coil 52 and prevent the first coil 51 and the second coil 52 from scattering. In this embodiment, the support sheet 70 includes a first support sheet 71 and a second support sheet 72. The first support piece 71 and the second support piece 72 are long pieces, and the lengths thereof may be set as needed. In this embodiment, the lengths of the first support piece 71 and the second support piece 72 are equal to the length of the stator 20. The first support plate 71 and the second support plate 72 are spaced apart from each other, and are respectively located outside the rotor 30 and inside the stator 20. The first and

second support pieces

71 and 72 are spaced apart from the rotor 30 so as not to interfere with the rotation of the rotor 30. The distances between the first support piece 71 and the second support piece 72 and the flat plate portion 63123 of the stator 20 may be set as needed, and in this embodiment, the first support piece and the second support piece are respectively attached to the flat plate portion 63123 of the stator 20. The widths of the first and

second support pieces

71 and 72 are related to the distance between the first and

second coils

51 and 52. One end of each of the first and

second support pieces

71 and 72 in the width direction abuts against the first coil 51, and the other end abuts against the second coil 52, so that the first and

second coils

51 and 52 can be abutted against the stator 20. In this embodiment, the first support piece 71 and the second support piece 72 are respectively abutted between two end edges of the first coil 51 and the second coil 52. In other embodiments, the first support piece 71 and the second support piece 72 may also abut on non-edge portions of the first coil 51 and the second coil 52. In order to match the shapes of the first coil 51 and the second coil 52 to avoid scattering, a first abutting inclined surface 711 is respectively disposed at two ends of the first supporting sheet 71 along the width direction, and a second abutting inclined surface 721 is respectively disposed at two ends of the second supporting sheet 72. The first abutting inclined surface 711 and the second abutting inclined surface 721 are oppositely arranged, face to the edges of the two ends of the first coil 51 and the second coil 52, and are respectively attached to the edges of the first coil 51 and the second coil 52 in shape. The first abutting inclined surface 711 and the second abutting inclined surface 721 are arranged in a slope manner, so that the first coil 51 and the second coil 52 can be prevented from scattering towards the rotor 30, and the safety of the rotation of the rotor 30 can be improved.

As shown in fig. 1 to 5, a housing 80 and an end cover 90 are provided outside the stator 20. The housing 80 is connected to the end cover 90 in a matching manner, and a cavity is formed inside the housing for accommodating the rotor 30, the stator 20, the central shaft 10, and the like.

As shown in fig. 1 to 5, the housing 80 is cylindrical and covers the stator 20. In order to reduce the volume of the whole device, the cross-sectional shape of the housing 80 is preferably matched with the cross-sectional shape of the stator 20, and in this embodiment, the cross-section of the housing 80 is in a racetrack shape. In order to enclose the stator 20, the first coil 51 and the second coil 52 inside, the length of the housing 80 should be greater than the lengths of the first coil 51 and the second coil 52.

As shown in fig. 1 to 5, one end of the housing 80 is open, and is used for being connected with the end cover 90 in an involutory manner. The other end of the housing 80 is provided with a circular bearing hole 81 for mounting a bearing 82. When the rotor 30, the stator 20, the center shaft 10, the magnet assembly 40, the first coil 51, the second coil 52 and the insulator 60 are installed in the housing 80, the protruding end 11 of the center shaft 10 passes through the bearing hole 81 and protrudes out of the housing 80. In order to facilitate the rotation of the central shaft 10, a bearing 82 is sleeved on the central shaft 10. The bearing 82 is installed at the bearing hole 81.

As shown in fig. 1 to 5, the end cap 90 is connected to the housing 80 in an involutory manner, and is used for sealing an end of the housing 80 and inserting the resilient piece 100. The end cap 90 has a cavity formed therein, which can hold the spring 100. The elastic sheet 100 is arranged between the central shaft 10 and the end cover 90: one end of the elastic sheet 100 is fixedly connected with the central shaft 10, for example, plugged together; the other end of the spring 100 is fixedly connected to the end cap 90. The elastic sheet 100 is in the shape of a long strip, which may be made of a metal material, and is used to assist the rotor 30 to reset.

As shown in fig. 1 to 5, in order to facilitate the connection of the lead wires, a wire through hole is further formed in the end cover 90, and the wire through hole penetrates through the outside and the inside of the end cover 90, so that the connection end of the first coil 51 and the second coil 52 in the housing assembly can be led out from the inside to the outside.

To prevent the wires of the first and

second coils

51, 52 from loosening, a first positioning slot 91 and a second positioning slot 92 are provided at an end of the end cap 90 facing the housing 80. The first positioning groove 91 is opposite to the first coil 51 and has a shape matching the shape of the end of the first coil 51. The second positioning groove 92 is opposite to the second coil 52 and has a shape matching the shape of the end of the second coil 52. When the end cap 90 is connected to the open end of the housing 80, the end of the first coil 51 is inserted into the first positioning slot 91, and the end of the second coil 52 is inserted into the second positioning slot 92, so that the ends of the first coil 51 and the second coil 52 are restrained and are not easy to loosen.

By this, just formed the utility model discloses a prevent small-size motor device that coil scatters: the central shaft 10 is sleeved in the rotor 30 and can synchronously rotate along with the rotor 30; the magnet group 40 is installed on the rotor 30, the stator 20 is sleeved outside the rotor 30, and the first pole shoe 21 and the second pole shoe 22 of the stator 20 face the centers of two adjacent magnets; the insulating member 60 is sleeved at two ends of the stator 20, and the first coil 51 and the second coil 52 are sleeved on the positioning groove 63 of the insulating member 60 and are not in contact with the first pole piece 21 and the second pole piece 22 respectively; the housing 80 is sleeved outside the stator 20 and is connected with the end cover 90 in an involution manner; one end of the elastic sheet 100 is connected with the central shaft 10, and the other end of the elastic sheet is fixed with the end cover 90; the extending end 11 of the central shaft 10 extends out of the shell 80; the first supporting piece 71 and the second supporting piece 72 are abutted against the edges of the two ends of the first coil 51 and the second coil 52 along the width direction, and the ends of the first coil 51 and the second coil 52 along the length direction are inserted into the first positioning groove 91 and the second positioning groove 92 of the end cover 90; the thread ends of the first coil 51 and the second coil 52 are led out from the thread holes on the end cover 90 and can be electrically connected with a power supply.

In use, when the first coil 51 and the second coil 52 are not energized, the rotor 30 is in a static state, and the first pole piece 21 and the second pole piece 22 of the stator 20 correspond to the positions between the magnets of the magnet group 40 and do not correspond to the magnets. When positive and negative square wave power supplies are connected to the first coil 51 and the second coil 52, the coils are energized to generate a magnetic field, so that the first pole shoe 21 and the second pole shoe 22 of the stator 20 have polarities, and the magnet group 40 with different polarities can be attracted through the change of magnetism, so that the rotor 30 rotates in a reciprocating manner, and high-frequency vibration is realized.

To the utility model discloses a prevent small-size motor device that coil scatters, its first coil 51 and the main part of second coil 52 not only can be propped up by first support piece 71 and second support piece 72, and the tip of first coil 51 and second coil 52 still can be restricted by end cover 90 moreover to make first coil 51 and second coil 52 be difficult to scatter, thereby can avoid the coil loose and influence the rotation of rotor 30. The utility model discloses a prevent small-size motor device that coil scatters has the advantage of dependable performance, security height, and it has very strong practicality.

While the invention has been described with reference to the above embodiments, the scope of the invention is not limited thereto, and the above components may be replaced with similar or equivalent elements known to those skilled in the art without departing from the concept of the invention.

Claims

1. The utility model provides a prevent small-size motor device that coil scatters, its includes center pin (10), rotor (30) of cover locating on center pin (10), locate magnet group (40) on rotor (30), locate stator (20) outside rotor (30), locate first coil (51) and second coil (52) between rotor (30) and stator (20), characterized in that be equipped with backing sheet (70) between first coil (51) and second coil (52), the one end of backing sheet (70) with first coil (51) butt, the other end of backing sheet (70) with second coil (52) butt, backing sheet (70) will first coil (51) and second coil (52) butt tightly on stator (20).

2. The small-sized motor device for preventing the coil from being scattered as claimed in claim 1, wherein the support piece (70) comprises a first support piece (71) and a second support piece (72), and the first support piece (71) and the second support piece (72) are spaced apart and abut between two end edges of the first coil (51) and the second coil (52), respectively.

3. The small-sized motor device for preventing the coil from scattering as claimed in claim 2, wherein a first abutting inclined surface (711) is respectively disposed at two ends of the first supporting piece (71), a second abutting inclined surface (721) is respectively disposed at two ends of the second supporting piece (72), and the first abutting inclined surface (711) and the second abutting inclined surface (721) are disposed opposite to each other and face edges of two ends of the first coil (51) and the second coil (52).

4. The small-sized motor device for preventing the coil from being scattered as claimed in claim 1, wherein the stator (20) is formed by laminating silicon steel sheets, the stator is cylindrical as a whole, a first pole piece (21) and a second pole piece (22) are symmetrically arranged on the inner wall of the stator (20), the first pole piece (21) and the second pole piece (22) are spaced relatively, the first coil (51) is sleeved on the first pole piece (21), and the second coil (52) is sleeved on the second pole piece (22).

5. The small-sized motor device for preventing the coil from scattering as claimed in claim 1, wherein a housing (80) is sleeved outside the stator (20), one end of the central shaft (10) extends out of the housing (80), an end cover (90) is connected to the other end of the housing (80) opposite to the extending end (11) of the central shaft (10) in an involutory manner, an elastic sheet (100) is arranged between the end cover (90) and the central shaft (10), one end of the elastic sheet (100) is fixedly connected with the central shaft (10), and the other end of the elastic sheet (100) is fixedly connected with the end cover (90).

6. The small-sized motor device for preventing the coil from being scattered as set forth in claim 5, wherein a first positioning groove (91) and a second positioning groove (92) are formed at an end of the end cap (90) facing the housing (80), the first positioning groove (91) is opposite to the first coil (51), the second positioning groove (92) is opposite to the second coil (52), an end of the first coil (51) is inserted into the first positioning groove (91), and an end of the second coil (52) is inserted into the second positioning groove (92).

7. The small-sized motor device for preventing the coil from scattering of claim 4,

the first coil (51) is in a ring shape, the center of the first coil is provided with a first positioning hole (511) matched with the first pole shoe (21) in shape, and the first pole shoe (21) is positioned in the first positioning hole (511);

the second coil (52) is in a ring shape, a second positioning hole (521) matched with the second pole shoe (22) in shape is formed in the center of the second coil, and the second pole shoe (22) is located in the second positioning hole (521).

8. The small-sized motor device for preventing the coil from being scattered as set forth in claim 4, wherein an insulating member (60) is respectively disposed at both open ends of the stator (20), one end of the insulating member (60) is respectively lapped over both ends of the stator (20), and the other end of the insulating member (60) covers the ends of the first pole piece (21) and the second pole piece (22) to isolate the first pole piece (21) and the second pole piece (22) from the first coil (51) and the second coil (52), respectively.

9. The small-sized motor device for preventing the coil from being scattered as claimed in claim 4, wherein a central shaft hole (31) is formed in the center of the rotor (30), and the central shaft (10) is sleeved in the central shaft hole (31) and can rotate synchronously with the rotor (30); a plurality of strip-shaped magnet slots (32) which are mutually spaced are symmetrically distributed on the outer wall of the rotor (30), and the magnet groups (40) are arranged in the magnet slots (32).

10. The small-sized coil-scattering prevention motor device as claimed in claim 9, wherein the magnet slots (32) are parallel to the central shaft (10), symmetrically distributed outside both sides of the first and second pole pieces (21, 22) and facing the first and second coils (51, 52), respectively.