WO2021134243A1

WO2021134243A1 - Linear vibration motor

Info

Publication number: WO2021134243A1
Application number: PCT/CN2019/130013
Authority: WO
Inventors: 马杰; 李子昂
Original assignee: 瑞声声学科技(深圳)有限公司; 瑞声科技（南京）有限公司
Priority date: 2019-12-30
Filing date: 2019-12-30
Publication date: 2021-07-08

Abstract

A linear vibration motor, comprising a housing (1), a vibration unit (2), an elastic assembly (3), and coil units (4) for driving the vibration unit (2) to vibrate along a first direction, a second direction, and a third direction. The vibration unit (2) comprises a magnetic steel unit (21) which is opposite to the coil unit (4) at an interval, the magnetic steel unit (21) comprises a first magnet portion (211) and a second magnet portion (212) which are magnetized along a magnetizing direction, and magnetic poles of the first magnet portion (211) and the second magnet portion (212) are opposite; an included angle between an interface of the first magnet portion (211) and the second magnet portion (212) and the first direction is not 90 degrees. The coil units (4) are respectively fixed to the two opposite sides of the housing (1) in the magnetizing direction, and the long axis or the short axis of each coil unit (4) is parallel to the interface; each coil unit (4) comprises an iron core (41) and a coil (42) wound on the outer side of the iron core (41). Compared with the related art, the linear vibration motor is good in vibration performance and high in reliability.

Description

Linear vibration motor

Technical field

The utility model relates to a motor, in particular to a linear vibration motor used in the field of mobile electronic products.

Background technique

With the development of electronic technology, portable consumer electronic products are becoming more and more popular, such as mobile phones, handheld game consoles, navigation devices or handheld multimedia entertainment equipment, etc. These electronic products generally use linear vibration motors for system feedback , Such as mobile phone call reminder, information reminder, navigation reminder, vibration feedback of game console, etc. Such a wide range of applications requires the vibration motor to have excellent performance and long service life.

The related art linear vibration motor includes a base having a housing space, a vibration unit, an elastic component fixed to the base and suspending the vibration unit in the housing space, and fixed to the base to drive the The coil unit vibrated by the vibrating unit interacts with the magnetic field generated by the vibrating unit through the electric field generated by the coil unit, thereby driving the vibrating unit to make a reciprocating linear motion to generate vibration. In order to achieve the bidirectional vibration effect, in the linear vibration motor of the related art, the magnetic steel extends along the diagonal direction of the base, and the magnetic steel is magnetized in an oblique position, and the coil unit is placed parallel to the side wall of the base.

technical problem

However, in the linear vibration motor of the related art, the above-mentioned magnetic steel is obliquely magnetized and the coil unit is arranged upright, so that part of the structure of the coil unit and the magnetic steel is not fully utilized, which limits the driving force formed by the two, resulting in The vibration effect is not good.

Therefore, it is necessary to provide a new linear vibration motor to solve the above-mentioned problems.

Technical solutions

The technical problem to be solved by the utility model is to provide a linear vibration motor that realizes bidirectional vibration and has good vibration performance.

In order to solve the above technical problems, the present invention provides a linear vibration motor, which includes a housing with a housing space, a vibration unit, and an elastic component fixed to the housing and suspended in the housing space. , And fixed to the housing to drive the vibrating unit in a first direction, a second direction, or along a plane formed by the first direction and the second direction and not in contact with the first direction A coil unit that vibrates in a third direction whose direction coincides with the second direction, and the first direction and the second direction are perpendicular to each other; the vibration unit includes spaced opposite and interacts with the coil unit to provide driving force The magnetic steel unit includes a first magnet portion and a second magnet portion that are magnetized along a magnetizing direction, and the first magnet portion and the second magnet portion have opposite magnetic poles, and the magnetizing direction Perpendicular to the plane formed by the first direction and the second direction; the interface between the first magnet part and the second magnet part forms an included angle of non-90 degrees with the first direction; the coil The unit includes an iron core fixed to the housing and located on at least one side of the vibrating unit along the magnetizing direction, and a coil wound around the iron core, the coil having a racetrack shape and the length of the coil The axis or minor axis is parallel to the interface.

Preferably, the iron core is strip-shaped, the length direction of the iron core is parallel to the long axis direction of the coil, and the thickness direction of the iron core is parallel to the magnetizing direction.

Preferably, the coil unit further includes a magnetic conductive sheet attached to a side of the coil away from the vibration unit, and the magnetic conductive sheet is connected to the iron core.

Preferably, the magnetic conductive sheet is provided with a relief opening extending inward from its periphery, and the welding lead of the coil extends through the relief opening.

Preferably, the vibrating unit further includes a mass, the mass is provided with a receiving through hole penetrating it along the magnetizing direction, the magnetic steel unit is received in the receiving through hole and fixed, so The elastic component is connected with the mass block.

Preferably, the coil unit is partially located in the receiving through hole.

Preferably, the mass block has a rectangular structure, including a short axis side parallel to the first direction and a long axis side parallel to the second direction; On opposite sides of the second direction, each of the elastic components includes a fixed arm that is fixed to the housing near one of the short axis sides and is spaced apart from the mass, and is opposite to the fixed arm. A first elastic arm whose ends are respectively bent and extended in a direction close to the adjacent short axis side, and an end of the first elastic arm away from the fixed arm is bent in a direction close to the adjacent long axis side An extended second elastic arm, and a connecting arm extending from the second elastic arm and fixed to the long axis side of the mass, the angle between the fixed arm and the first elastic arm is At an obtuse angle, the first elastic arm and the second elastic arm are spaced from the mass block to form a suspended arrangement.

Preferably, the linear vibration motor further includes a damping member sandwiched between the elastic component and the corner of the mass block, each of the damping components corresponding to the adjacent first of the elastic components A resilient arm abuts against the second resilient arm.

Preferably, the housing includes a bottom wall, a side wall bent and extended from the edge of the bottom wall, and a cover plate covering an end of the side wall away from the bottom wall. The bottom wall and the side wall And the cover plate encloses the accommodating space, the coil unit is fixed to the bottom wall and the cover plate respectively, and the distances between the elastic components and the cover plate are different.

Preferably, the linear vibration motor further includes a limit block fixed to at least one of the bottom wall and the cover plate, and the limit block includes a block that is fixed to the housing and extends along the first direction. The limit block body and the limit block extension body extending along the second direction from the limit block body, the mass block is provided with a limit groove that cooperates with the limit block extension body, the limit block The bit block extension body extends into the limiting groove.

Preferably, the limiting block is located on a side of the mass block away from the fixed arm adjacent to the limiting block.

Beneficial effect

Compared with the related art, in the linear vibration motor of the present invention, the coil unit is arranged to drive the vibration unit to vibrate in a first direction, a second direction, or along a plane formed by the first direction and the second direction. The magnet unit of the vibrating unit is arranged as a first magnet part and a second magnet part that are magnetized along the magnetizing direction and have opposite magnetic poles, and vibrate in a third direction that does not coincide with the first direction and the second direction, The magnetization direction is perpendicular to the plane formed by the first direction and the second direction, wherein the interface between the first magnet portion and the second magnet portion forms a non-90 degree with the first direction And make the long axis or the short axis of the coil unit parallel to the interface. In the above structure, the arrangement of the coil unit and the magnetic steel unit makes full use of the interaction force between the two to realize the vibration in the first and second directions orthogonal to each other, or the third direction, the drive is large, and the improvement is effective. The coil unit interacts with the magnetic steel unit to generate a driving force parallel to the normal direction of the interface. The driving force generates a partial driving force along the normal first direction and the second direction of the respective surface, thereby achieving The driving vibration unit vibrates in the first direction or the second direction or along the first direction that is located on the plane formed by the first direction and the second direction and does not overlap with the first direction and the second direction It vibrates in three directions, and the driving effect in two directions is better.

Description of the drawings

Figure 1 is a schematic diagram of the three-dimensional structure of the linear vibration motor of the utility model;

Figure 2 is an exploded schematic diagram of a part of the three-dimensional structure of the linear vibration motor of the utility model;

Figure 3 is a front view of a part of the three-dimensional structure of the linear vibration motor of the utility model;

Figure 4 is a front view of another part of the three-dimensional structure of the linear vibration motor of the utility model

Figure 5 is a cross-sectional view taken along the line A-A in Figure 1;

Fig. 6 is a cross-sectional view taken along the line B-B in Fig. 1.

Embodiments of the present invention

The utility model will be further described below in conjunction with the drawings and the embodiments.

The utility model provides a linear vibration motor 100. For the convenience of description, an XYZ three-axis coordinate system is established. As shown in Figure 2, the X-axis direction is defined as the first direction, and the Y-axis direction is defined as the second direction. , Define the magnetization direction along the Z axis, where the first direction and the second direction are two different vibration directions, and the magnetization direction is the thickness direction of the linear vibration motor, then the first direction, the second direction and The magnetizing directions are perpendicular to each other.

Please refer to FIGS. 1-6 at the same time, the linear vibration motor 100 includes a housing 1 having a housing space 10, a vibration unit 2 located in the housing space 10, and fixed to the housing 1 and the vibration unit 2 The elastic component 3 suspended in the accommodating space 10 is fixed to the housing 1 to drive the vibrating unit 2 in the first direction, the second direction, or along the first direction and the second direction. A third-direction vibrating coil unit 4 on a plane formed by the direction and not overlapping the first direction and the second direction, a damping member 5 and a stop block 6 arranged in the containing space.

The housing 1 includes a bottom wall 11, a side wall 12 bent and extended from the edge of the bottom wall 11, and a cover plate 13 covering an end of the side wall 12 away from the bottom wall. The bottom wall 11, the side wall 12 and the cover plate 13 enclose the receiving space 10. The vibration unit 2 includes a magnetic steel unit 21 and a mass 22.

The magnetic steel unit 21 is opposed to and interacts with the coil unit 4 to provide driving force.

Specifically, the magnetic steel unit 21 includes at least two parts with opposite magnetic poles. For example, in this embodiment, the magnetic steel unit 21 includes a first magnet portion 211 and a second magnet portion 212 that are magnetized along the magnetizing direction. And the magnetic poles of the first magnet part 211 and the second magnet part 212 are opposite, that is, the magnetizing direction of the magnetic steel unit 21 is the thickness direction of the linear vibration motor 100, which is the same as the first direction and the first direction. The plane formed by the two directions is vertical. The interface 213 between the first magnet portion 211 and the second portion 212 forms an included angle other than 90 degrees with the first direction, or an included angle other than 90 degrees with the second direction.

The mass 22 is used to increase the weight of the vibration unit 2 and improve the vibration performance. In this embodiment, the mass block 22 is provided with a receiving through hole 221 passing through it along the magnetizing direction, the magnetic steel unit 21 is received in the receiving through hole 221 and fixedly formed, and the elastic component 3 and The mass block 22 is connected, and the vibration unit 2 is suspended in the containing space 10 by fixing with the mass block 22.

In this embodiment, the mass 22 has a rectangular structure and includes a short axis side parallel to the first direction and a long axis side parallel to the second direction.

The elastic components 3 are arranged on opposite sides of the mass block 22 opposite to each other. In this embodiment, the elastic component 3 includes two elastic components 3 respectively located on opposite sides of the mass block parallel to its short axis, that is, on opposite sides of the mass block 22 in the second direction.

Specifically, each of the elastic components 3 includes a fixed arm 31 fixed to the side of the housing 1 close to one of the short axis sides and connected to the mass 22, and a fixed arm 31 formed by opposite ends of the fixed arm 31 The first elastic arms 32 are respectively bent and extended in the direction close to the adjacent short axis side, and the end of the first elastic arm 32 away from the fixed arm 31 is bent in the direction close to the adjacent long axis side. A second elastic arm 33 that is folded and extended, and a connecting arm 34 that extends from the second elastic arm 33 and is fixed to the long axis side of the mass 22. Wherein, the angle between the fixed arm 31 and the first elastic arm 32 is an obtuse angle, and the first elastic arm 32 and the second elastic arm 33 are spaced apart from the mass 22 to form a suspended arrangement. The distances between the elastic components 3 and the cover plate 13 are different.

The coil unit 4 includes an iron core 41 fixed to the housing 1 and located on at least one side of the vibrating unit 2 along the magnetizing direction (Z-axis direction), and a coil wound around the iron core 41 42.

Specifically, the coil unit 4 is fixed to the bottom wall 11 and the cover plate 13 respectively.

In this embodiment, the coil unit 4 includes two coil units and is respectively fixed on opposite sides of the housing 1 along the magnetizing direction (Z-axis direction).

Specifically, the iron core 41 has a strip shape, the coil 42 has a racetrack shape, and the long axis or the short axis of the coil 42 is parallel to the interface. The longitudinal direction of the iron core 41 is parallel to the longitudinal direction of the coil 42, and the thickness direction of the iron core 41 is parallel to the magnetizing direction.

More preferably, in order to reduce the thickness of the linear vibration motor 100 and make its design thinner, the coil unit 4 is partially located in the receiving through hole 221.

In this embodiment, in order to reduce magnetic leakage, the coil unit 4 further includes a magnetic conductive sheet 43 attached to the side of the coil 42 away from the vibration unit 2, and the magnetic conductive sheet 43 and the iron The core 41 is connected. The coil unit 4 is fixed to the housing 1 through a magnetic conductive sheet 43.

More preferably, the magnetic conductive sheet 43 is provided with a relief opening 431 extending inward from its periphery, and the welding lead of the coil 42 extends through the relief opening 431 and is led to an external power source by the FPC.

The damping member 5 is sandwiched between the elastic component 3 and the corner of the mass block 22.

The damping member 5 includes four and is located at the four corners of the mass 22 respectively. Each of the damping members 5 abuts against the adjacent first elastic arm 32 and the second elastic arm 33 of the corresponding elastic component 3. That is, the damping member 5 has parts in contact with the mass 22 and the elastic component 3 in both the first direction and the second direction, so as to realize the mass 22 in the first direction (X-axis direction) and the second direction. (Y-axis direction) or the third direction (direction on the plane formed by the X-axis and the Y-axis and not coincident with the X-axis and the Y-axis) provides damping to improve its stability and reliability.

The limiting block 6 is fixed to at least one of the bottom wall 11 and the cover plate 13. The limiting block 6 is located on the side of the short axis away from the fixed arm 31 adjacent to the limiting block 6.

In this embodiment, the limiting block 6 includes two and is respectively disposed on opposite sides of the short axis of the mass block 22, for limiting the vibration unit 22 in the first direction, the second direction, and the third direction. Bit to improve its reliability.

Specifically, the limiting block 6 includes a limiting block body 61 fixed to the housing 1 and extending in the first direction, and a limiting block body 61 extending in the second direction. The block extension 62, for example, forms a "T" shape. The mass block 22 is provided with a limiting groove 222 that cooperates with the limiting block extension 62, and the limiting block extension 62 extends into the limiting groove 222. The limit block body 61 realizes the displacement limit when the vibration unit 2 vibrates in the second direction, and the limit block extension 62 realizes the displacement limit when the vibration unit 2 vibrates in the first direction. The limit block body 61 Together with the limit block extension 62, the displacement limit of the vibration unit 2 when vibrating in the third direction is realized.

More preferably, in order to further reduce the size of the linear vibration motor 100 in the magnetizing direction (its thickness direction, that is, the Z-axis direction), it reduces its thickness. In this embodiment, the two elastic components 3 are superimposed on each other along the magnetizing direction, and the limit block bodies 61 of the two limit blocks 6 are respectively fixed to the housing 1 along the On two opposite sides of the magnetizing direction, the two limiting slots 222 are respectively opened on the opposite sides of the mass 22 along the too strong direction. Therefore, in the magnetizing direction, the limit block 6 and the elastic component 3 make full use of the thickness space of the mass block 22 along the magnetizing direction.

As shown in Figure 5, when the coil 42 is energized, the energized coil 42 cuts the magnetic lines of induction to form ampere force. At the same time, the iron core 41 is polarized due to the energization of the coil 42 and has polarity. The two coil units 4 The two iron cores 41 respectively interact with the magnetic steel unit 21 to form an electromagnetic force; and the ampere force and the electromagnetic force work together to form a driving force along the normal direction of the interface 213, as shown in FIG. The driving force has driving force components in the first direction and the second direction, so that the driving force is in the first direction, the second direction, and is located on the plane formed by the first direction and the second direction and does not coincide with the The vibration in the third direction in which the first direction and the second direction coincide provides driving force, when the frequency of the current (that is, the frequency of the driving signal) is close to the resonance frequency of the linear vibration motor 100 in the first direction or the second direction At this time, the mode in the first direction or the second direction is excited to form the main direction of movement. When the frequency of the drive signal corresponds to the resonance frequency in the first direction and the resonance frequency in the second direction at the same time, the vibrating unit 2 moves along the first direction (X) and the second vibration (Y) mode The states are simultaneously excited. At this time, under the action of the resultant force, the vibrating unit 2 vibrates along the third direction.

However, the above-mentioned structure arrangement greatly utilizes the interaction between the coil unit 4 and the magnetic steel unit 21, which effectively increases the driving force and improves the vibration performance.

It should be understood that the shapes of the masses, iron cores and other components described above are only used as examples and are not limited to the present invention. The iron cores can also be cylindrical or other shapes, and the masses can also be round, square or other regular shapes. Or the irregular shape only needs to be able to fix the magnet part and connect with the elastic component. Compared with the related art, in the linear vibration motor of the present invention, the coil unit is arranged to drive the vibration unit to vibrate in a first direction, a second direction, or along a plane formed by the first direction and the second direction. The magnet unit of the vibrating unit is arranged as a first magnet part and a second magnet part that are magnetized along the magnetizing direction and have opposite magnetic poles, and vibrate in a third direction that does not coincide with the first direction and the second direction, The magnetization direction is perpendicular to the plane formed by the first direction and the second direction, wherein the interface between the first magnet portion and the second magnet portion forms a non-90 degree with the first direction And make the long axis or the short axis of the coil unit parallel to the interface. In the above structure, the arrangement of the coil unit and the magnetic steel unit makes full use of the interaction force between the two to realize the vibration in the first and second directions orthogonal to each other, or the third direction, the drive is large, and the improvement is effective. The coil unit interacts with the magnetic steel unit to generate a driving force parallel to the normal direction of the interface. The driving force generates a partial driving force along the normal first direction and the second direction of the respective surface, thereby achieving The driving vibration unit vibrates in the first direction or the second direction or along the first direction that is located on the plane formed by the first direction and the second direction and does not overlap with the first direction and the second direction It vibrates in three directions, and the driving effect in two directions is better.

The above are only the embodiments of the utility model, and do not limit the patent scope of the utility model. Any equivalent structure or equivalent process transformation made by using the description and drawings of the utility model, or directly or indirectly applied to other Related technical fields are included in the scope of patent protection of the utility model in the same way.

Claims

A linear vibration motor includes a housing with a housing space, a vibration unit, an elastic component fixed to the housing and suspending the vibration unit in the housing space, and a housing fixed to the housing to drive the The vibration unit is located along a first direction, a second direction, or along a third direction that is located on a plane formed by the first direction and the second direction and does not overlap with the first direction and the second direction. A coil unit vibrating in a direction, the first direction and the second direction are perpendicular to each other, characterized in that:

The vibration unit includes a magnetic steel unit that is spaced apart from the coil unit and interacts with each other to provide a driving force. The magnetic steel unit includes a first magnet part and a second magnet part that are magnetized in a magnetizing direction. The magnetic poles of a magnet part and the second magnet part are opposite, and the magnetizing direction is perpendicular to the plane formed by the first direction and the second direction; The interface and the first direction form an included angle other than 90 degrees;

The coil unit includes an iron core fixed to the housing and located on at least one side of the vibrating unit along the magnetizing direction, and a coil wound around the iron core, the coil is in a racetrack shape and the The long or short axis of the coil is parallel to the interface.
The linear vibration motor according to claim 1, wherein the iron core is strip-shaped, the length direction of the iron core is parallel to the long axis direction of the coil, and the thickness direction of the iron core is parallel to the longitudinal direction of the coil. The magnetizing direction is parallel.
The linear vibration motor according to claim 1 or 2, wherein the coil unit further comprises a magnetic conductive sheet attached to a side of the coil away from the vibration unit, the magnetic conductive sheet and the Iron core connection.
The linear vibration motor according to claim 3, wherein the magnetic conductive sheet is provided with a relief opening extending inward from its periphery, and the welding lead of the coil extends through the relief opening.
The linear vibration motor according to claim 1, wherein the vibration unit further comprises a mass, and the mass is provided with a receiving through hole penetrating therethrough along the magnetizing direction, and the magnetic steel unit receives It is fixed in the receiving through hole, and the elastic component is connected with the mass block.
The linear vibration motor of claim 5, wherein the coil unit is partially located in the receiving through hole.
The linear vibration motor of claim 5, wherein the mass has a rectangular structure, including a short axis side parallel to the first direction and a long axis side parallel to the second direction; Elastic components are respectively located on opposite sides of the masses along the second direction, and each of the elastic components includes a side fixed to the housing close to one of the short axis sides and spaced apart from the mass The fixed arm, the first elastic arm bent and extended from the opposite ends of the fixed arm in the direction close to the adjacent short axis side, and the end of the first elastic arm away from the fixed arm is close to A second elastic arm bent and extended in the direction adjacent to the long axis side, and a connecting arm extending from the second elastic arm and fixed to the long axis side of the mass, the fixed arm and the The included angle between the first elastic arms is an obtuse angle, and both the first elastic arm and the second elastic arm are spaced from the mass block to form a suspended arrangement.
The linear vibration motor according to claim 7, wherein the linear vibration motor further comprises a damping member sandwiched between the elastic component and the corner of the mass block, each of the damping members and Correspondingly, the adjacent first elastic arm and the second elastic arm in the elastic component abut against each other.
The linear vibration motor according to claim 7, wherein the housing comprises a bottom wall, a side wall bent and extended from the edge of the bottom wall, and a cover provided on an end of the side wall away from the bottom wall. The cover plate, the bottom wall, the side walls and the cover plate enclose the containing space, the coil unit is respectively fixed to the bottom wall and the cover plate, and each of the elastic components is connected to the cover The distance between the plates is not the same.
The linear vibration motor of claim 9, wherein the linear vibration motor further comprises a limit block fixed to at least one of the bottom wall and the cover plate, and the limit block includes a A limit block body fixed to the housing and extending along the first direction and a limit block extension body extending from the limit block body in the second direction, the mass block is provided with the limit block A limiting groove matched with a block extension body, and the limiting block extension body extends into the limiting groove.
The linear vibration motor according to claim 10, wherein the limiting block is located on a side of the short axis away from the fixed arm adjacent to the limiting block.