Linear vibration motor

Abstract

Provided in the present utility model is a linear vibration motor, comprising a shell, and a stator and a vibrator which are received in the shell, and an elastic member for suspending the vibrator in the shell. The vibrator comprises a mass block fixedly connected to the elastic member and having a through hole, and a magnetic circuit system received in the through hole. The magnetic circuit system comprises first magnetic steel arranged on one side of the stator in a direction perpendicular to a vibration direction of the vibrator and second magnetic steel arranged on the other side of the stator in the direction perpendicular to the vibration direction of the vibrator, wherein the first magnetic steel and the second magnetic steel extend in parallel and are symmetrically arranged with a geometric center of the stator as the center, the first magnetic steel comprises a first magnetic steel portion, an orthographic projection of which in the direction perpendicular to the vibration direction of the vibrator is located outside the second magnetic steel, and the second magnetic steel comprises a second magnetic steel portion, an orthographic projection of which in the direction perpendicular to the vibration direction of the vibrator is located outside the first magnetic steel. The design of such an asymmetric magnetic circuit structure can improve the offset problem of the mounting position of the stator leading to nonlinear vibration of the vibration motor, and the test stability and yield are improved.

Description

A linear vibration motor Technical Field

[0001] The utility model relates to a linear vibration motor, in particular to a magnetic circuit structure of the linear vibration motor. Background Art

[0002] A linear motor is a transmission device that converts electrical energy directly into mechanical energy for linear motion. It is also known as a linear motor, linear actuator, or push rod motor. Linear motors typically consist of a vibrator and a stator. They typically achieve reciprocating motion of the vibrator under the action of the Ampere force, without the need for gears or other transmission mechanisms. Due to their simple structure, high acceleration, and high precision, linear motors are widely used in various manufacturing and processing technologies.

[0003] The magnetic circuit of the linear vibration motor in the prior art is designed with a symmetrical structure, but the stator is easily offset in the installation position when it is fixed, thereby causing nonlinear vibration of the vibration motor.

[0004] Therefore, it is necessary to provide a new linear vibration motor to solve the above technical problems. Technical issues

[0005] The purpose of the utility model is to provide a linear vibration motor with better stability and yield. Technical Solutions

[0006] The technical solution of the present invention is as follows: The present invention provides a linear vibration motor, comprising a shell having a receiving space, a stator and a vibrator received in the receiving space, and an elastic member fixed to the shell and suspending the vibrator in the receiving space, the vibrator comprising a mass block fixedly connected to the elastic member and having a through hole, and a magnetic circuit system received in the through hole, the magnetic circuit system comprising a first magnetic steel arranged on one side of the stator perpendicular to the vibration direction of the vibrator and a second magnetic steel arranged on the other side of the stator perpendicular to the vibration direction of the vibrator, the first magnetic steel and the second magnetic steel extending parallel to each other and being centrally symmetrically arranged with the geometric center of the stator as the center, the first magnetic steel comprising a first magnetic steel portion whose orthographic projection along the vibration direction perpendicular to the vibrator is located outside the second magnetic steel, and the second magnetic steel comprising a second magnetic steel portion whose orthographic projection along the vibration direction perpendicular to the vibrator is located outside the first magnetic steel.

[0007] Preferably, the length of the first magnetic steel portion is equal to the length of the second magnetic steel portion.

[0008] Preferably, the ratio of the length of the first magnetic steel portion to the length of the first magnetic steel does not exceed 1 / 10, and the ratio of the length of the second magnetic steel portion to the length of the second magnetic steel does not exceed 1 / 10.

[0009] Preferably, the ratio of the length of the first magnetic steel portion to the length of the first magnetic steel is between 1 / 25 and 1 / 20, and the ratio of the length of the second magnetic steel portion to the length of the second magnetic steel is between 1 / 25 and 1 / 20.

[0010] Preferably, the magnetic circuit system includes a third magnetic steel arranged on one side of the stator in the vibration direction of the vibrator and a fourth magnetic steel arranged on the other side of the stator in the vibration direction of the vibrator, and the third magnetic steel and the fourth magnetic steel are axially symmetrically arranged with the geometric center of the stator as the center axis.

[0011] Preferably, the distance between the first magnetic steel and the stator is equal to the distance between the second magnetic steel and the stator, and the distance between the third magnetic steel and the stator is equal to the distance between the fourth magnetic steel and the stator.

[0012] Preferably, the magnetic circuit system includes a first magnetic conductive sheet sandwiched between the first magnetic steel and the mass block, a second magnetic conductive sheet sandwiched between the second magnetic steel and the mass block, a third magnetic conductive sheet sandwiched between the third magnetic steel and the mass block, and a fourth magnetic conductive sheet sandwiched between the fourth magnetic steel and the mass block.

[0013] Preferably, the first magnetic conductive sheet is aligned with the first magnetic steel and has the same length as the first magnetic steel, the second magnetic conductive sheet is aligned with the second magnetic steel and has the same length as the second magnetic steel, the third magnetic conductive sheet is aligned with the third magnetic steel and has the same length as the third magnetic steel, and the fourth magnetic conductive sheet is aligned with the fourth magnetic steel and has the same length as the fourth magnetic steel.

[0014] Preferably, the elastic member includes an elastic arm spaced apart from the mass block, a first connecting arm bent and extended from one end of the elastic arm and fixed to the mass block, and a second connecting arm bent and extended from the other end of the elastic arm and fixed to the shell. The linear vibration motor also includes foam sandwiched between the elastic arm and the mass block. Beneficial effects

[0015] The beneficial effect of the present invention is that the present invention provides a linear vibration motor with an asymmetric magnetic circuit structure. Compared with the prior art, this asymmetric magnetic circuit structure design can improve the situation where the vibration motor vibrates nonlinearly when the installation position of the stator is offset, thereby improving the stability and yield of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. Among them:

[0017] FIG1 is a schematic diagram of the three-dimensional structure of a linear vibration motor provided by an embodiment of the present utility model;

[0018] FIG2 is a schematic diagram of the three-dimensional structure of the linear vibration motor shown in FIG1 with the lower cover removed;

[0019] FIG3 is an exploded view of the linear vibration motor shown in FIG1 ;

[0020] FIG4 is a cross-sectional view of the linear vibration motor shown in FIG1 along line AA;

[0021] FIG5 is a schematic structural diagram of the magnetic circuit system and the stator in the linear vibration motor shown in FIG1 . Modes for Carrying Out the Invention

[0022] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] Please refer to Figures 1-5 at the same time. The present invention provides a linear vibration motor 100, which includes a housing 1, a stator 2 installed in the housing 1, a vibrator 3, an elastic member 4 for suspending the vibrator 3 in the housing 1, a foam 5 arranged between the elastic member 4 and the vibrator 3, and a circuit board 6 partially fixed in the housing 1. The circuit board 6 is fixed to the housing 1 and electrically connected to the stator 2. The vibration direction of the vibrator 3 is defined as the Y-axis direction, and the vibration direction perpendicular to the vibrator 3 is defined as the X-axis direction. In this embodiment, the linear vibration motor 100 is rectangular, the major axis direction is the Y-axis direction, and the minor axis direction is the X-axis direction.

[0024] The housing 1 includes a lower cover 11 and an upper cover 12 covering the lower cover 11. The stator 2 is fixed to a side of the lower cover 11 close to the upper cover 12. The lower cover 11 and the upper cover 12 are fixedly arranged to form a receiving space 10 for accommodating the stator 2, the vibrator 3 and the elastic member 4. The housing 1 also includes a groove 101 for allowing the other end of the circuit board 6 to extend to the outside.

[0025] The stator 2 includes an iron core 21 and a coil 22 wound around the iron core 21 .

[0026] The vibrator 3 includes a mass block 31 having a through hole 310 and a magnetic circuit system 32 accommodated in the through hole 310. The magnetic circuit system 32 includes a first magnetic steel 301 arranged on one side of the stator 2 in the X-axis direction, a second magnetic steel 302 arranged on the other side of the stator 2 in the X-axis direction, a third magnetic steel 303 arranged on one side of the stator 2 in the Y-axis direction, and a fourth magnetic steel 304 arranged on the other side of the stator 2 in the Y-axis direction. The first magnetic steel 301 and the second magnetic steel 302 extend parallel to the Y-axis direction and are arranged symmetrically around the geometric center of the stator 2. The third magnetic steel 303 and the fourth magnetic steel 304 extend parallel to the X-axis direction and are arranged symmetrically around the geometric center of the stator 2.

[0027] The distance D1 between the first magnetic steel 301 and the stator 2, the distance D2 between the first magnetic steel 302 and the stator 2, the distance D3 between the third magnetic steel 303 and the stator 2, and the distance D4 between the fourth magnetic steel 304 and the stator 2 satisfy the relationship D1=D2, D3=D4, and D1<D3.

[0028] The first magnetic steel 301 includes a first magnetic steel portion 3011 whose orthographic projection along the X-axis is located outside the second magnetic steel 302. The second magnetic steel 302 includes a second magnetic steel portion 3021 whose orthographic projection along the X-axis is located outside the first magnetic steel 301. The ratio of the length of the first magnetic steel portion 3011 to the length of the first magnetic steel 301 is no more than 1 / 10, and the ratio of the length of the second magnetic steel portion 3021 to the length of the second magnetic steel 302 is no more than 1 / 10. Preferably, in this embodiment, the length of the first magnetic steel portion 3011 accounts for 4.5% of the total length of the first magnetic steel 301, and the length of the second magnetic steel portion 3021 accounts for 4.5% of the total length of the second magnetic steel.

[0029] The magnetic circuit system 32 also includes a first magnetic conductive sheet 311 sandwiched between the first magnetic steel 301 and the mass block 31, a second magnetic conductive sheet 312 sandwiched between the second magnetic steel 302 and the mass block 31, a third magnetic conductive sheet 313 sandwiched between the third magnetic steel 303 and the mass block 31, and a fourth magnetic conductive sheet 314 sandwiched between the fourth magnetic steel 304 and the mass block 31. The first magnetic conductive sheet 311 is aligned with the first magnetic steel 301 and has the same length as the first magnetic steel 301, the second magnetic conductive sheet 312 is aligned with the second magnetic steel 302 and has the same length as the second magnetic steel 302, the third magnetic conductive sheet 313 is aligned with the third magnetic steel 303 and has the same length as the third magnetic steel 303, and the fourth magnetic conductive sheet 314 is aligned with the fourth magnetic steel 304 and has the same length as the fourth magnetic steel 304.

[0030] The elastic member 4 includes an elastic arm 41 spaced apart from the mass block 31 , a first connecting arm 42 bent and extended from one end of the elastic arm 41 and fixed to the mass block 31 , and a second connecting arm 43 bent and extended from the other end of the elastic arm 41 and fixed to the housing 1 .

[0031] The linear vibration motor 100 includes a first welding piece 71 for welding the first connecting arm 42 to the mass block 31 through a welding spot, and a second welding piece 72 for welding the second connecting arm 43 to the upper cover 12 through a welding spot.

[0032] The linear vibration motor 100 further includes a limit block 8 , which is fixed to the lower cover 11 and is used to limit the displacement of the vibrator 3 .

[0033] Compared with the related art, the present invention provides a linear vibration motor, comprising a shell having a receiving space, a stator and a vibrator received in the receiving space, and an elastic member fixed to the shell and suspending the vibrator in the receiving space, the vibrator comprising a mass block fixedly connected to the elastic member and having a through hole, and a magnetic circuit system received in the through hole, the magnetic circuit system comprising a first magnetic steel arranged on one side of the stator perpendicular to the vibration direction of the vibrator and a second magnetic steel arranged on the other side of the stator perpendicular to the vibration direction of the vibrator, the first magnetic steel and the second magnetic steel extending parallel to each other and being centrally symmetrically arranged with the geometric center of the stator as the center, the first magnetic steel comprising a first magnetic steel portion whose orthographic projection is located outside the second magnetic steel along the direction perpendicular to the vibration direction of the vibrator, the second magnetic steel comprising a second magnetic steel portion whose orthographic projection is located outside the first magnetic steel along the direction perpendicular to the vibration direction of the vibrator, the asymmetric magnetic circuit structure designed in the present invention can improve the nonlinear vibration of the stator when the installation position is offset, which is beneficial to improving the stability and yield of the test.

[0034] The above is only an embodiment of the present invention. It should be pointed out that those skilled in the art can make improvements without departing from the inventive concept of the present invention, but these improvements are all within the scope of protection of the present invention.

Claims

1. A linear vibration motor, comprising a housing having a receiving space, a stator and a vibrator received in the receiving space, and an elastic member fixed to the housing and suspending the vibrator in the receiving space, wherein the vibrator comprises a mass block fixedly connected to the elastic member and having a through hole, and a magnetic circuit system received in the through hole, wherein the magnetic circuit system comprises a first magnetic steel arranged on one side of the stator in a direction perpendicular to the vibration direction of the vibrator and a second magnetic steel arranged on the other side of the stator in a direction perpendicular to the vibration direction of the vibrator, characterized in that: The first magnetic steel extends parallel to the second magnetic steel and is symmetrically arranged with the geometric center of the stator as the center. The first magnetic steel includes a first magnetic steel portion located outside the second magnetic steel along an orthographic projection perpendicular to the vibration direction of the vibrator, and the second magnetic steel includes a second magnetic steel portion located outside the first magnetic steel along an orthographic projection perpendicular to the vibration direction of the vibrator.

2. The linear vibration motor according to claim 1, characterized in that: The length of the first magnetic steel portion is equal to the length of the second magnetic steel portion.

3. The linear vibration motor according to claim 2, characterized in that: The ratio of the length of the first magnetic steel portion to the length of the first magnetic steel does not exceed 1 / 10, and the ratio of the length of the second magnetic steel portion to the length of the second magnetic steel does not exceed 1 / 10.

4. The linear vibration motor according to claim 3, characterized in that: The ratio of the length of the first magnetic steel portion to the length of the first magnetic steel is in a range between 1 / 25 and 1 / 20, and the ratio of the length of the second magnetic steel portion to the length of the second magnetic steel is in a range between 1 / 25 and 1 / 20.

5. The linear vibration motor according to claim 4, characterized in that: The magnetic circuit system includes a third magnetic steel arranged on one side of the stator in the vibration direction of the vibrator and a fourth magnetic steel arranged on the other side of the stator in the vibration direction of the vibrator, and the third magnetic steel and the fourth magnetic steel are symmetrically arranged with the geometric center of the stator as the center axis.

6. The linear vibration motor according to claim 5, characterized in that: The distance between the first magnetic steel and the stator is equal to the distance between the second magnetic steel and the stator, and the distance between the third magnetic steel and the stator is equal to the distance between the fourth magnetic steel and the stator.

7. The linear vibration motor according to claim 5, characterized in that: The magnetic circuit system includes a first magnetic conductive sheet sandwiched between the first magnetic steel and the mass block, a second magnetic conductive sheet sandwiched between the second magnetic steel and the mass block, a third magnetic conductive sheet sandwiched between the third magnetic steel and the mass block, and a fourth magnetic conductive sheet sandwiched between the fourth magnetic steel and the mass block.

8. The linear vibration motor according to claim 7, characterized in that: The first magnetic conductive sheet is aligned with the first magnetic steel and has the same length as the first magnetic steel, the second magnetic conductive sheet is aligned with the second magnetic steel and has the same length as the second magnetic steel, the third magnetic conductive sheet is aligned with the third magnetic steel and has the same length as the third magnetic steel, and the fourth magnetic conductive sheet is aligned with the fourth magnetic steel and has the same length as the fourth magnetic steel.

9. The linear vibration motor according to claim 1, characterized in that: The elastic member includes an elastic arm spaced apart from the mass block, a first connecting arm bent and extended from one end of the elastic arm and fixed to the mass block, and a second connecting arm bent and extended from the other end of the elastic arm and fixed to the shell. The linear vibration motor also includes foam sandwiched between the elastic arm and the mass block.

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