CN210201684U

CN210201684U - Vibration motor and electric toothbrush

Info

Publication number: CN210201684U
Application number: CN201920952343.6U
Authority: CN
Inventors: Fan Zhang; 张帆; Longbo Liu; 刘龙波; Cheng Chen; 陈诚
Original assignee: Aberkin Electric Manufacturing (shenzhen) Co Ltd
Current assignee: Aberkin Electric Manufacturing (shenzhen) Co Ltd
Priority date: 2019-06-19
Filing date: 2019-06-19
Publication date: 2020-03-27
Anticipated expiration: 2029-06-19

Abstract

The utility model discloses a vibration motor, which comprises a stator component and a rotor component, wherein the rotor component is arranged in the stator component and can swing relative to the stator component, the stator component comprises a stator core, a wire frame sleeved on the stator core and a winding wound on the wire frame, the rotor component comprises magnetic steel, a retainer for fixing the magnetic steel and a rotating shaft fixedly connected with the retainer, the stator core comprises a circular arc-shaped tooth top and a tooth body connected with the middle part of the radial outer side of the tooth top, and the middle part of the radial inner side of the tooth top is provided with a groove; the magnetic steel comprises a first magnetic pole part and a second magnetic pole part which are axially symmetrical, the magnetic poles of the first magnetic pole part and the second magnetic pole part are opposite, the first magnetic pole part and the second magnetic pole part jointly form a plane opposite to the radial inner side of the tooth top at intervals, and the ratio range of the central angle corresponding to the plane and the central angle corresponding to the tooth top is 1-3/2. The utility model discloses a motor magnetic energy conversion rate can improve. The utility model discloses still provide the electric toothbrush including aforementioned vibrating motor.

Description

Vibration motor and electric toothbrush

Technical Field

The utility model relates to a drive field, concretely relates to vibrating motor and electric toothbrush.

Background

Electric toothbrushes are increasingly popular among people because of their advantages of time and labor saving, good cleaning effect, etc. In principle, electric toothbrushes include both rotary and vibratory types. The vibrating toothbrush comprises a magnetic suspension vibrating motor which can generate high-frequency swing perpendicular to the brush handle direction so as to brush teeth. A typical oscillating toothbrush motor includes a stator assembly, and a rotor assembly disposed within and oscillatable relative to the stator assembly. How to improve the magnetic energy conversion rate of the motor is a constantly sought goal in the field.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present invention is directed to a vibration motor and an electric toothbrush that can solve the above problems to some extent.

To this end, an aspect of the present invention provides a vibration motor, including a stator assembly and a rotor assembly arranged in the stator assembly and capable of swinging relative to the stator assembly, wherein the stator assembly includes a stator core, a bobbin sleeved on the stator core, and a winding wound on the bobbin, the rotor assembly includes a magnetic steel, a holder for fixing the magnetic steel, and a rotating shaft fixedly connected to the holder, the stator core includes a circular arc-shaped tooth top and a tooth body connected to a middle portion of a radial outer side of the tooth top, and a groove is formed in a middle portion of a radial inner side of the tooth top; the magnet steel comprises a first magnetic pole part and a second magnetic pole part which are axially symmetrical, the magnetic poles of the first magnetic pole part and the second magnetic pole part are opposite, the first magnetic pole part and the second magnetic pole part jointly form a plane opposite to the radial inner side of the tooth top at intervals, and the ratio range of the central angle corresponding to the plane and the central angle corresponding to the tooth top is 1-3/2.

In some embodiments, the holder includes a circular arc-shaped first wall, and a first outer side wall and a second outer side wall which intersect with two circumferential sides of the first wall respectively and are planar, a first accommodating groove is formed in a middle portion of the first wall along a radial inward recess, and the magnetic steel is accommodated in the first accommodating groove.

In some embodiments, the bobbin includes a circular arc-shaped second inner wall, and a first inner side surface and a second inner side surface that extend from a radial inner side of the second inner wall, the first inner side surface and the second inner side surface are opposite at intervals and are both planar, a second receiving groove is formed in a middle portion of the second inner wall in a recessed manner along an axial direction, and a tooth top of the stator core is supported in the second receiving groove.

In some embodiments, the first wall and the second inner wall are concentric and opposite at intervals, a central angle corresponding to the first wall is smaller than that of the second inner wall, and junctions of the first wall and the first and second outer side walls are suitable for abutting against the first and second inner side faces respectively.

In some embodiments, the rotor assembly oscillates through an angle in the range of 3 ° to 15 °.

In some embodiments, stator module still includes a casing, the casing include convex third wall and respectively with the circumference both sides of third wall are crossing and are planar first lateral wall and second lateral wall, stator core still include with the convex tooth root of the radial outer wall connection of tooth body, the radial outside of tooth root with the third wall supports, the circumference both sides of tooth root respectively with first lateral wall with the second lateral wall supports.

In some embodiments, the wire rack further includes a first abutting block and a second abutting block vertically connected to the first inner side surface and the second inner side surface, respectively, the first abutting block abuts against the first side wall of the housing, and the second abutting block abuts against the second side wall of the housing.

In some embodiments, the radial cross-section of the groove is circular arc, and the ratio of the diameter of the groove to the width of the tooth body is 1/4-3/4.

In some embodiments, a ratio of a diameter of the groove to a thickness of the tooth tip is between 1/2-3/2.

On the other hand, the utility model also provides an electric toothbrush, including aforementioned vibrating motor and with the brush head that vibrating motor's pivot is connected.

The utility model discloses a motor, the ratio scope of the central angle of the tooth top of its stator core and the planar central angle of correspondence of magnet steel is 1-3/2, and this kind of arrangement can not interfere under the wobbling condition of rotor subassembly in the assurance, has improved the magnetic energy conversion rate of motor, has improved the efficiency that converts magnetic energy into mechanical energy promptly, and the motor drives load wobbling ability and can improve.

Drawings

Fig. 1 is a perspective view of a vibration motor according to an embodiment of the present invention.

Fig. 2 is an exploded view of the vibration motor shown in fig. 1.

Fig. 3 is a longitudinal sectional view of the vibration motor shown in fig. 1.

Fig. 4 is a transverse sectional view of the vibration motor shown in fig. 1.

Fig. 5 is a partially exploded view of a stator assembly of the vibration motor shown in fig. 1, with parts omitted.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and specific embodiments, so that the technical solutions and the advantages thereof will be more clearly understood. It is to be understood that the drawings are provided for purposes of illustration and description only and are not intended as a definition of the limits of the invention, but the dimensions shown in the drawings are for convenience and are not to be taken as limiting the scale.

Referring to fig. 1 to 3, a vibration motor 100 according to an embodiment of the present invention includes a stator assembly 10 and a rotor assembly 20 that is swingable with respect to the stator assembly 10. The stator assembly 10 has a receiving cavity 11 formed therein for receiving the rotor assembly 20. The stator assembly 10 includes a hollow housing 30, a stator core 40 fixedly connected in the housing 30, a bobbin 50 disposed on a surface of the stator core 40, and a winding 60 wound on the bobbin 50. The rotor assembly 20 includes a magnetic steel 70, a holder 80 for fixing the magnetic steel 70, and a rotating shaft 90 fixedly connected to the holder 80. One end of the shaft 90 is rotatably connected to an end cap 92 through a bearing 91, wherein the end cap 92 is fixedly connected to the bottom end of the housing 30. The other end of the shaft 90 is connected to an output shaft 93, and the output shaft 93 is rotatably connected to the top end of the housing 30 through another bearing 94 for transmitting torque to a load.

As shown in fig. 2 to 4, in the present embodiment, the rotor assembly 20 includes two pieces of magnetic steel 70 in a rectangular parallelepiped shape. The two pieces of magnetic steel 70 are fixed in the holder 80 and symmetrically arranged with respect to the rotation shaft 90. Specifically, the holder 80 is substantially cylindrical, and the rotating shaft 90 penetrates the holder 80 with their central axes coinciding with each other. Preferably, the retainer 80 is integrally formed with the shaft 90 by over-molding to improve the bonding strength between the two. The retainer 80 includes two opposite circular arc-shaped

first walls

81, 82, and a first outer side wall 83 and a second outer side wall 84 respectively connecting opposite circumferential sides of the two

first walls

81, 82. The first outer side wall 83 and the second outer side wall 84 are each planar. The

first walls

81 and 82 are recessed at the middle to form a first receiving groove 85 for receiving the magnetic steel 70. The magnetic steel 70 and the bottom wall of the first receiving groove 85 can be fixedly connected in an adhesion manner. The magnetic steel 70 includes a first magnetic pole portion 71 and a second magnetic pole portion 72 that are axisymmetrical (left-right symmetric in fig. 4), and the first magnetic pole portion 71 and the second magnetic pole portion 72 have opposite magnetic poles, as shown in fig. 4 as an N pole and an S pole. The first and second magnetic pole portions 71 and 72 may be formed by charging neodymium iron boron permanent magnets. The central axis of the magnetic steel 70 is aligned with the neutral axis of the rotating shaft 90, so that the magnetic forces on the left and right sides of the magnetic steel 70 are symmetrical when swinging around the rotating shaft 90. Preferably, the magnetic steel 70 abuts against two opposite side walls of the first receiving groove 85 to improve the reliability of the alignment of the central axis of the magnetic steel 70 with the neutral axis of the rotating shaft 90. The magnetic steel 70 can also abut against two opposite end walls of the first accommodating groove 85, so that the stability of the magnetic steel 70 is improved, and the axial looseness of the magnetic steel 70 is prevented. Preferably, two opposite end walls of the first receiving groove 85 are respectively formed with a stopper 86, and the stopper 86 is located at the radial outer side of the magnetic steel 70 and opposite to the radial outer side to prevent the magnetic steel 70 from being removed from the first receiving groove 85. The stopper 86 may be an elastic member having a thickness variation, for example, a wedge shape, which becomes thicker toward the magnetic steel 70, so that the magnetic steel 70 can be quickly fitted into the first receiving groove 85.

As shown in fig. 4 and 5, in the present embodiment, the stator core 40 includes a rectangular parallelepiped tooth body 41, and a tooth crest 42 and a tooth root 43 connected to a radially inner wall and a radially outer wall of the tooth body 41, respectively. The tooth body 41 is located between a middle position of the tooth top 42 and a middle position of the tooth bottom 43. The addendum 42 and the dedendum 43 have arc shapes, and a central angle corresponding to the addendum 42 is smaller than a central angle corresponding to the dedendum 43. Preferably, the tooth crest 42 corresponds to a central angle of 86 °. The plane 73 of the magnetic steel 70 facing the tooth crest 42 is opposite to the radial inner side of the tooth crest 42 at intervals, and the ratio range of the central angle corresponding to the plane 73 to the central angle corresponding to the tooth crest 42 is 1-3/2, preferably, the central angle corresponding to the plane 73 in the embodiment is equal to the central angle corresponding to the tooth crest 42, that is, the radial extension lines of the two circumferential sides of the tooth crest 42 and the center of the rotating shaft 90 pass through the left end and the right end of the plane 73 of the magnetic steel 70.

When the winding 60 of the stator assembly 10 is energized with alternating current, the winding 60 generates an alternating magnetic field, the stator core 40 conducts magnetic conduction, and the magnetic steel 70 drives the retainer 80 to swing left and right under the action of magnetic force according to the principle that like poles repel each other and opposite poles attract each other. In this embodiment, the central angle of the tooth top 42 of the stator core 40 is equal to the central angle of the plane 73 of the magnetic steel 70, and this arrangement improves the efficiency of the motor for converting magnetic energy into mechanical energy without interfering with the swing of the rotor assembly 20, so that the capability of the motor for driving the load to swing can be improved. The tooth tip 42 is formed with a groove 420 formed by recessing from the radially inner side to the radially outer side. The groove 420 has a circular arc-shaped cross section and axially penetrates the radially inner side of the tooth top 42. The radial inner side surface of the tooth top 42 is effectively separated into two polar surfaces by the groove 420, one of the polar surfaces corresponds to the first magnetic pole part 71 of the magnetic steel 70, the other polar surface corresponds to the second magnetic pole part 72 of the magnetic steel 70, the problem of magnetic field disorder in the middle of the radial inner side surface of the tooth top 42 is effectively prevented, and the motor swings more stably. Preferably, the ratio of the diameter of the recess 420 to the width of the tooth body 41 is between 1/4-3/4. The ratio of the diameter of the groove 420 to the thickness of the tooth top 42 is between 1/2-3/2. Preferably, the shortest distance from the side wall of the groove 420 to the connection between the tooth body 41 and the tooth top 42 is greater than the thickness of the tooth top 42, so that the magnetic flux in the tooth body 41 flows into the tooth top 42, and the magnetic energy conversion rate is higher. In the present embodiment, the diameter of the groove 420 is equal to half of the width of the tooth body 41 and equal to the thickness of the tooth crest 42.

The bobbin 50 includes two branching bobbins 51, and each branching bobbin 51 supports a stator core 40. Each of the wire-distributing frames 51 includes two opposite sub-frames 52, and the two sub-frames 52 respectively abut against two axial ends of one stator core 40. The creel 52 includes spaced apart opposing second inner walls 53, second outer walls 54, and a bridge portion 55 connected between the second inner walls 53 and the second outer walls 54. The second inner wall 53 and the second outer wall 54 are both circular arc shaped. The middle portion of the second inner wall 53 is recessed in the axial direction to form an arc-shaped second receiving groove 530 for receiving the tooth top 42 of the stator core 40. A central angle between both circumferential sidewalls of the second receiving groove 530 is preferably 87 °, that is, larger than a central angle of the tooth crest 42 of the stator core 40, so that a gap is formed between the stator core 40 and the second receiving groove 530. A saddle 550 is formed on the bridge 55 for positioning the stator core 40. Saddle 550 includes two spaced apart opposing intermediate segments 551, and inner and

outer abutments

552 and 553 that connect radially inner and outer walls, respectively, of intermediate segments 551. The sub-bobbin 52 further includes a first inner side surface 56 and a second inner side surface 57 extending from the radial inner side of the second inner wall 53, and a first abutting block 58 and a second abutting block 59 extending from the first inner side surface 56 and the second inner side surface 57 in the radial direction. The first inner side surface 56 and the second inner side surface 57 are opposite at intervals and are planar. The first abutting block 58 and the second abutting block 59 are rectangular. The first abutting block 58 is vertically connected to the first inner side surface 56. The second abutting block 59 is vertically connected to the second inner side surface 57.

The housing 30 includes two

third walls

31, 32 of circular arc shape arranged oppositely, and a first side wall 33 and a second side wall 34 respectively connecting opposite circumferential sides of the two

third walls

31, 32. The first side wall 33 and the second side wall 34 are planar.

When assembling the stator assembly 10, the two sub-bobbins 52 are firstly sleeved on the two axial ends of the stator core 40. Specifically, the tooth body 41, the tooth top 42, and the tooth bottom 43 of the stator core 40 are supported by the bridge portion 55 of the sub-bobbin 52, the second receiving groove 530 of the second inner wall 53, and the second outer wall 54, respectively. At this time, the intermediate section 551 of the saddle portion 550 of the sub-bobbin 52 abuts against both sides of the tooth body 41 of the stator core 40, the inner abutting portion 552 abuts against the radially outer side of the tooth tip 42 of the stator core 40, and the outer abutting portion 553 abuts against the radially inner side of the tooth root 43 of the stator core 40. The windings 60 are then placed over the corresponding two saddles 550 of the stator core 40. In particular, two windings 60 corresponding to the two stator cores 40 may be simultaneously wound on one multi-winding-head winding machine, respectively, to improve the winding efficiency. After the winding is finished, the first and second abutting blocks 58 and 59 of the two branch frames 51 are overlapped together, and then placed into the inner cavity 35 of the housing 30, so that the radial outer sides of the tooth roots 43 of the two stator cores 40 abut against the

third walls

31 and 32 of the housing 30, and the two circumferential sides of each tooth root 43 abut against the first side wall 33 and the second side wall 34 of the housing 30. The root 43 and the shell 30 may be bonded together by glue. Meanwhile, the first and second abutting blocks 58 and 59 of the bobbin 50 abut against the middle portions of the first and

second side walls

33 and 34 of the casing 30, respectively, thereby improving the overall strength of the stator assembly 10.

When the rotor assembly 20 is assembled in the accommodating cavity 11 of the stator assembly 10, the circular arc-shaped

first walls

81 and 82 of the retainer 80 are respectively concentric with and spaced from the circular arc-shaped second inner walls 53 of the two branch frames 51, and the central angles corresponding to the

first walls

81 and 82 are smaller than the central angle of the second inner walls 53. The first outer side wall 83 of the holder 80 is parallel to and opposed to the first inner side surface 56 of the bobbin 50, and the second outer side wall 84 of the holder 80 is parallel to and opposed to the second inner side surface 57 of the bobbin 50. When the rotor assembly 20 swings to the maximum angle leftward, the junction of the first wall 81 and the first outer side wall 83 of the retainer 80 abuts against the first inner side surface 56 of one of the branching frames 51, and the junction of the first wall 82 and the second outer side wall 84 of the retainer 80, which are opposite to the first wall 81, abuts against the second inner side surface 57 of the other branching frame 51; when the rotor assembly 20 swings rightwards to the maximum angle, the junction of the first wall 81 and the second outer side wall 84 of the retainer 80 abuts against the second inner side surface 57 of one of the branch frames 51, and the junction of the first wall 82 and the first outer side wall 83 of the retainer 80, which are opposite to the first wall 81, abuts against the first inner side surface 56 of the other branch frame 51, so that the swing angle of the rotor assembly 20 is limited through the design of a mechanical structure, and the rotor assembly 20 can swing more stably within a limited angle range. The rotor assembly 20 preferably oscillates through an angle in the range of 3 to 15. Since a gap is formed between the tooth top 42 of the stator core 40 and the sidewall of the second receiving groove 530, the influence of vibration on the stator core 40 caused by mechanical impact of the holder 80 on the bobbin 50 can be effectively reduced.

The vibration motor 100 in this embodiment is particularly suitable for application to an electric toothbrush. Specifically, a brushhead is inserted onto the output shaft 93 of the vibrating toothbrush.

The above description is only a preferred embodiment of the present invention, the protection scope of the present invention is not limited to the above listed embodiments, any person skilled in the art can obviously obtain simple changes or equivalent substitutions of the technical solutions within the technical scope of the present invention.

Claims

1. A vibration motor comprises a stator assembly and a rotor assembly which is arranged in the stator assembly and can swing relative to the stator assembly, wherein the stator assembly comprises a stator core, a wire frame sleeved on the stator core and a winding wound on the wire frame; the magnet steel comprises a first magnetic pole part and a second magnetic pole part which are axially symmetrical, the magnetic poles of the first magnetic pole part and the second magnetic pole part are opposite, the first magnetic pole part and the second magnetic pole part jointly form a plane opposite to the radial inner side of the tooth top at intervals, and the ratio range of the central angle corresponding to the plane and the central angle corresponding to the tooth top is 1-3/2.

2. The vibration motor according to claim 1, wherein the holder includes a first wall having an arc shape, and a first outer sidewall and a second outer sidewall that intersect with both circumferential sides of the first wall and are planar, a first receiving groove is formed in a middle portion of the first wall along a radial inward recess, and the magnetic steel is received in the first receiving groove.

3. The vibration motor of claim 2, wherein the bobbin includes a circular arc-shaped second inner wall, and a first inner side surface and a second inner side surface extending from a radial inner side of the second inner wall, the first inner side surface and the second inner side surface are opposite at intervals and are both planar, a second receiving groove is formed in a middle portion of the second inner wall in a recessed manner along an axial direction, and a tooth crest of the stator core is supported by the second receiving groove.

4. The vibration motor of claim 3, wherein the first wall and the second inner wall are concentric and opposite at intervals, a central angle corresponding to the first wall is smaller than that of the second inner wall, and junctions of the first wall and the first and second outer side walls are adapted to abut against the first and second inner side surfaces, respectively.

5. The vibration motor of claim 4 wherein said rotor assembly oscillates through an angle in the range of 3 ° to 15 °.

6. The vibration motor of claim 3, wherein the stator assembly further comprises a housing, the housing comprises a third wall having a circular arc shape, and a first sidewall and a second sidewall intersecting circumferential sides of the third wall respectively and being planar, the stator core further comprises a circular arc-shaped tooth root connected to a radial outer wall of the tooth body, a radial outer side of the tooth root abuts against the third wall, and circumferential sides of the tooth root abuts against the first sidewall and the second sidewall respectively.

7. The vibration motor of claim 6, wherein the bobbin further comprises a first abutting block and a second abutting block vertically connected to the first inner side surface and the second inner side surface, respectively, the first abutting block abutting against the first side wall of the housing, and the second abutting block abutting against the second side wall of the housing.

8. The vibration motor of claim 1, wherein the radial cross-section of the groove is circular arc, and the ratio of the diameter of the groove to the width of the tooth body is 1/4-3/4.

9. The vibration motor of claim 2, wherein a ratio of a diameter of the groove to a thickness of the tooth top is between 1/2-3/2.

10. An electric toothbrush comprising a vibration motor according to any one of claims 1 to 9 and a brush head connected to a rotating shaft of the vibration motor.