A strong vibration type linear vibration motor and its assembly method

Abstract

The present disclosure relates to the technical field of linear vibration motors, and in particular to a strong vibration type linear vibration motor and an assembly method thereof, wherein the motor comprises a housing, a vibrator and a stator, wherein the housing is hollow and has two through-set ends; the vibrator comprises an elastic sheet whose edge is fixed in the housing, and a main magnetic steel symmetrically fixed on both sides of the elastic sheet; the stator comprises a coil symmetrically fixed at both ends of the housing, and the size of the coil is configured to allow the main magnetic steel to extend into the coil; wherein the housing comprises a first shell and a second shell along its through-set direction, and the first shell and the second shell have a viscoelastic layer on the fixed surface facing the elastic sheet; when the two coils are synchronously connected with alternating current, the vibrator performs reciprocating linear vibration towards the two ends of the housing. The present disclosure improves the magnetic flux of the magnetic circuit and the amplitude of the vibrator by symmetrically setting the two sides, and by setting the viscoelastic layer, not only the vibration mode curve of the vibrator is smoother, but also the service life of the elastic sheet is improved and the vibration noise is reduced.

Description

Technical Field

[0001] The present disclosure relates to the technical field of linear vibration motors, and in particular to a strong vibration type linear vibration motor and an assembly method thereof. Background Art

[0002] Linear vibration motors are used in mobile phones, tablets, car touch panels and other products, and tactile feedback is achieved through the vibration of linear vibration motors;

[0003] In the related technologies known to the inventor, linear vibration motors mostly include an elastic sheet, a vibrator fixed on the elastic sheet, and a stator for driving the vibrator to vibrate, and the stator and the vibrator are mostly driven by the principle of electromagnetic induction; however, when implementing the above solution, the inventor found that the stiffness of the linear vibration motor is only related to the elastic element, resulting in a constant vibration effect of the linear vibration motor when working, and a poor vibration experience;

[0004] The information disclosed in this background technology section is only intended to deepen the understanding of the overall background technology of the present disclosure, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art known to those skilled in the art. Summary of the invention

[0005] In view of at least one of the above technical problems, the present disclosure provides a strong vibration type linear vibration motor and an assembly method thereof, which adopts a symmetrical stator and vibrator to maximize the amplitude, and by adding a viscoelastic layer on both sides of the elastic sheet, the vibration type curve generated by the vibration is smoother, the width of the resonance frequency band is increased, and a certain amount of noise can also be absorbed.

[0006] According to a first aspect of the present disclosure, there is provided a strong vibration type linear vibration motor, comprising a housing, a vibrator and a stator.

[0007] The shell is hollow and has two ends that are connected through it;

[0008] The vibrator comprises an elastic sheet with an edge fixed in the housing, and main magnetic steels symmetrically fixed on both sides of the elastic sheet;

[0009] The stator includes a coil symmetrically fixed at two ends of the housing, and the size of the coil is configured to allow the main magnetic steel to extend into the coil;

[0010] Wherein, the shell includes a first shell and a second shell along its through direction, the elastic sheet is fixed on the mating surface of the first shell and the second shell, and the first shell and the second shell have a viscoelastic layer on the fixing surface facing the elastic sheet; when the two coils are synchronously passed with alternating current, the vibrator performs reciprocating linear vibration toward the two ends of the shell.

[0011] In some embodiments of the present disclosure, the mating surfaces of the first shell and the second shell are arranged to be stepped, so that the outer wall of either one extends toward the other.

[0012] In some embodiments of the present disclosure, an annular groove is provided on the mating surfaces of the first shell and the second shell, and the annular groove is used for fixing or filling the viscoelastic layer.

[0013] In some embodiments of the present disclosure, the bottom of the annular groove of the first shell and / or the second shell further has a positioning column protruding toward the upper surface of the annular groove, and the elastic sheet has a positioning hole matching the positioning column.

[0014] In some embodiments of the present disclosure, the viscoelastic layer is formed by filling soft glue into the annular groove.

[0015] In some embodiments of the present disclosure, the elastic sheet has an arc-shaped hole inside that gradually extends toward the center, so that the elastic sheet forms a circumferential fixing portion, an elastic arm extending inward from the circumferential fixing portion, and a central fixing portion connected to the elastic arm, and the main magnet is fixed on the central fixing portion.

[0016] In some embodiments of the present disclosure, the vibrator further includes a mass block, a secondary magnetic steel and a pole piece;

[0017] The mass block is fixed between the central fixing portion and the main magnetic steel, the auxiliary magnetic steel is fixed on the pole piece, and the pole piece is fixed on the main magnetic steel.

[0018] In some embodiments of the present disclosure, the stator also includes a positioning flange and a skeleton, the positioning flange is fixed on the end faces of the first shell and the second shell, the positioning flange is hollow and extends inward, the skeleton is cylindrical and fixed on the part of the positioning flange extending inward, and the coil is fixed on the skeleton.

[0019] In some embodiments of the present disclosure, a fixing groove is provided on the end faces of the first shell and the second shell, a limiting portion is provided in the fixing groove, a limiting hole matching the limiting portion is provided on the positioning flange, and the viscoelastic layer is fixed in the fixing groove for connection with the positioning flange.

[0020] According to a second aspect of the present disclosure, there is also provided a method for assembling the strong vibration type linear vibration motor according to any one of the first aspects, comprising the following steps:

[0021] Laser scanning the end faces and the butt joint faces of the first shell and the second shell to increase the surface roughness;

[0022] Filling a viscous material on the butt joint surface and end surface of the first shell and the second shell to form a viscoelastic layer;

[0023] Fixing the main magnetic steel on the elastic sheet, fixing the elastic sheet on the first shell or the second shell, and fixing the coil on the end surfaces of the first shell and the second shell;

[0024] The first shell and the second shell are buckled together and connected by welding.

[0025] The beneficial effects of the present disclosure are as follows: the present disclosure improves the magnetic flux of the magnetic circuit and the amplitude of the vibrator through a symmetrical stator magnetic circuit design and symmetrically arranges the vibrator on both sides of the elastic sheet, thereby improving the vibration feeling of the user during use, and through the arrangement of the viscoelastic layer, not only the vibration mode curve of the vibrator is made smoother, but also the service life of the elastic sheet is improved and the vibration noise is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 It is a schematic cross-sectional three-dimensional structure diagram of a strong vibration type linear vibration motor in an embodiment of the present disclosure;

[0028] Figure 2 is an axial cross-sectional view of a strong vibration type linear vibration motor according to an embodiment of the present disclosure;

[0029] Figure 3 In the embodiments of the present disclosure Figure 2 A local enlarged view of point A in FIG.

[0030] Figure 4 It is a schematic diagram of the structure of the elastic sheet in the embodiment of the present disclosure;

[0031] Figure 5 is a schematic structural diagram of a vibrator in an embodiment of the present disclosure;

[0032] Figure 6 It is a schematic diagram of the exploded structure of the strong vibration type linear vibration motor in the embodiment of the present disclosure;

[0033] Figure 7 It is a schematic diagram of an exploded structure of a connection structure between a positioning flange and a first housing in an embodiment of the present disclosure;

[0034] Figure 8 It is a flowchart of the steps of the assembly method of the strong vibration type vibration motor in the embodiment of the present disclosure;

[0035] Fig. 9 Schematic diagram of the light spot path when laser scanning is performed on the surface of the annular groove in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments.

[0037] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present disclosure. The terms used in the specification of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0039] like Figures 1 to 7 The strong vibration type linear vibration motor shown includes a housing 10, a vibrator 20 and a stator 30, wherein:

[0040] The housing 10 is hollow and has two through-holes. In the embodiment of the present disclosure, the housing 10 is made of plastic or metal. Figure 2 As shown in the figure, the housing 10 is a cylindrical structure, which is connected from top to bottom. Of course, it should be pointed out here that the embodiment of the present disclosure does not limit the cross-sectional shape of the housing 10. Those skilled in the art can set the housing 10 to a rectangular or other structural form as needed, as long as both ends are opened, it falls within the protection scope of the present disclosure;

[0041] The vibrator 20 includes an elastic sheet 21 whose edge is fixed in the housing 10, and main magnetic steels 22 symmetrically fixed on both sides of the elastic sheet 21; Figure 2 In the embodiment of the present disclosure, the housing 10 is divided into a first housing 11 and a second housing 12, and the elastic sheet 21 is fixed between the first housing 11 and the second housing 12. When the elastic sheet 21 is fixed, the circumference of the elastic sheet 21 is fixed to the first housing 11 and the second housing 12, and the rest of the elastic sheet 21 is suspended in the air, so as to facilitate the up and down vibration of the elastic sheet 21.

[0042] The stator 30 includes a coil 31 symmetrically fixed at both ends of the housing 10, and the size of the coil 31 is configured to allow the main magnet 22 to extend into the coil 31; it should be noted here that in the embodiment of the present disclosure, there are multiple ways to fix the coil 31, for example, it can be directly fixed on the inner wall of the housing 10, or fixed in the form of a positioning flange 32 as described below; by setting the size of the coil 31 in a way that the main magnet can enter, the vibration amplitude of the main magnet 22 is increased without increasing the volume of the housing 10, thereby increasing the vibration sense;

[0043] In the embodiments of the present disclosure, please refer to Figures 1 to 3 As shown in , the first shell 11 and the second shell 12 have a viscoelastic layer 40 on the fixing surface facing the elastic sheet 21; the viscoelastic layer 40 here has at least two functions, one function is to support the fixing of the elastic sheet 21, and the other function is to facilitate the connection between the first shell 11 and the second shell 12. In the embodiment of the present disclosure, the viscoelastic layer 40 is made of a material that has both elasticity and viscosity, such as soft glue or a double-backed adhesive pad, so that the first shell 11 and the second shell 12 are connected through the viscoelastic layer 40 and the elastic sheet 21, and the elastic sheet 21 is flexibly fixed; through this flexible fixation, compared with the rigid fixation of the elastic sheet 21 in the prior art, not only the damage of the elastic sheet 21 during vibration is reduced, but also the system damping of the vibrator 20 is further enhanced, the fatigue life of the elastic sheet 21 is improved, and the curve of the vibrator 20 during vibration is smoother, and compared with the rigid connection, the vibration noise is also reduced;

[0044] In the embodiment of the present disclosure, when the motor is working, when the two coils 31 are synchronously supplied with alternating current, the vibrator 20 performs reciprocating linear vibrations toward the two ends of the housing 10, thereby achieving the transmission of vibration sensation;

[0045] In the above embodiment, by designing the symmetrical stator 30 magnetic circuit and arranging the vibrator 20 symmetrically on both sides of the elastic sheet 21, the magnetic flux of the magnetic circuit and the amplitude of the vibrator 20 are increased, thereby improving the vibration feeling of the user during use. In addition, by setting the viscoelastic layer 40, not only the vibration mode curve of the vibrator 20 is made smoother, but also the service life of the elastic sheet 21 is increased and the vibration noise is reduced.

[0046] In the embodiment of the present disclosure, in order to improve the reliability and accuracy of the docking between the first shell 11 and the second shell 12, as shown in FIG. Figure 2 and Figure 3As shown in , the mating surfaces of the first shell 11 and the second shell 12 are set to be stepped, so that the outer wall of either of them extends toward the other. With this arrangement, when the first shell 11 and the second shell 12 are mated, only the stepped part needs to be buckled, so that the centering reliability of the first shell 11 and the second shell 12 can be ensured, and it is also convenient for the elastic sheet 21 to be kept in the center position when it is fixed;

[0047] Furthermore, in the embodiment of the present disclosure, in order to further facilitate the fixation of the elastic sheet 21 and the viscoelastic layer 40, the first shell 11 and the second shell 12 have an annular groove 12a on their joint surfaces, and the annular groove 12a is used to fix or fill the viscoelastic layer 40. In one embodiment of the present disclosure, the viscoelastic layer 40 is formed by filling the annular groove 12a with soft glue. Due to the setting of the annular groove 12a, space is provided for the molding of the soft glue; in the embodiment of the present disclosure, as Figure 3 and Figure 4 As shown in , in order to further improve the reliability of fixing the elastic sheet 21, the bottom of the annular groove 12a of the first shell 11 and / or the second shell 12 also has a positioning column 12b protruding toward the upper surface of the annular groove 12a, and the elastic sheet 21 has a positioning hole matching the positioning column 12b. The positioning column 12b here can be set alone in the annular groove 12a of the first shell 11, or can be set alone in the annular groove 12a of the second shell 12, or the positioning column 12b can be set on both. In this way, not only can the accuracy of positioning the elastic sheet 21 be improved, but due to the setting of the positioning column 12b, the elastic sheet 21 can be prevented from rotating during the reciprocating vibration of the elastic sheet 21, thereby improving the service life of the vibration motor.

[0048] The specific structure of the elastic sheet 21 is as follows Figure 4 As shown in the figure, the elastic sheet 21 has a circular hole inside that gradually extends toward the center, so that the elastic sheet 21 forms a circumferential fixing portion 21b, an elastic arm 21c extending inward from the circumferential fixing portion 21b, and a central fixing portion 21d connected to the elastic arm 21c, and the main magnetic steel 22 is fixed on the central fixing portion 21d. Through this arrangement, the length of the elastic arm 21c is extended as much as possible, thereby further improving the vibration amplitude and performance of the vibrator 20, and can improve the reliability of the fixation of the vibrator 20 and the main magnetic steel 22;

[0049] In the embodiment of the present disclosure, in order to further improve the vibration performance of the vibrator 20, as Figure 2 and Figure 5As shown in , the vibrator 20 further includes a mass block 23, a secondary magnetic steel 25 and a pole piece 24; the mass block 23 is fixed between the central fixing portion 21d and the main magnetic steel 22, the secondary magnetic steel 25 is fixed on the pole piece 24, and the pole piece 24 is fixed on the main magnetic steel 22. In this way, by adding the mass block 23, the weight of the vibrator 20 is increased, and by adding the pole piece 24 and the secondary magnetic steel 25, the magnetic flux is increased, thereby making the overall vibration performance more superior;

[0050] In one embodiment of the present disclosure, Figure 2 and Figure 6 As shown in the figure, regarding the fixing structure of the coil 31, the stator 30 also includes a positioning flange 32 and a skeleton 33. The positioning flange 32 is fixed on the end faces of the first shell 11 and the second shell 12. The positioning flange 32 is hollow and extends inward. The skeleton 33 is cylindrical and fixed on the part of the positioning flange 32 extending inward. The coil 31 is fixed on the skeleton 33. In this way, when fixing, it is only necessary to fix the coil 31 on the skeleton 33, and fix the skeleton 33 on the positioning flange 32, and finally fix the fixing flange on both ends of the first shell 11 and the second shell 12 to achieve the fixing of the coil 31. This arrangement has a simple structure, is easy to implement, and is reliable in fixing.

[0051] Furthermore, in the embodiment of the present disclosure, in order to improve the convenience of fixing the coil 31, as shown in FIG. Figure 7 As shown in the figure, the end surfaces of the first shell 11 and the second shell 12 are provided with a fixing groove 11a, a limiting portion 11b is provided in the fixing groove 11a, a limiting hole 32a matching the limiting portion 11b is provided on the positioning flange 32, and the viscoelastic layer 40 is fixed in the fixing groove 11a for connection with the positioning flange 32. With the arrangement of the above-mentioned structural form, it is only necessary to mold the viscoelastic layer 40 in the fixing groove 11a, and directly match and fix the positioning flange 32 with the positioning portion, so as to realize the fixed connection between the positioning flange 32 and the first shell 11 and the second shell 12.

[0052] In another aspect of the embodiments of the present disclosure, a method for assembling the above-mentioned strong vibration type linear vibration motor is also provided. Figure 8 As shown in , the following steps are included:

[0053] S10: Laser scans the end faces and the butt joint faces of the first shell 11 and the second shell 12 to increase the surface roughness. It should be noted that in order to improve the connection strength between the viscoelastic layer 40 and the shell 10, the present invention uses laser scanning to melt, vaporize, splash and re-solidify the material surface, thereby increasing the roughness of the material surface and increasing the contact area of ​​the glue. When performing laser scanning in the embodiment of the present invention, it is necessary to set the spot diameter and spacing according to the length of the bonding surface. In the embodiment of the present invention, a pulse fiber laser marking machine is used for scanning. The specific parameters set are power 10~30W, pulse width 10~240ms, scanning frequency 20~80kHz, scanning speed 0.3~1m / s, laser spot diameter 50~60μm, and when performing scanning, such as Fig. 9 As shown in the figure, the circumference of the annular groove 12a is L, the spot diameter is d, and during the specific scanning, the spacing D between the two rows of spots is set to D=L / (3~6)d to avoid the laser energy causing the material surface to be excessively melted and smooth; by setting the above parameters, the final material surface roughness is increased, and the bonding force of the glue is enhanced.

[0054] S20: Filling a viscous material on the butt joint surface and the end surface of the first shell 11 and the second shell 12 to form a viscoelastic layer 40; the viscous material here can be soft glue, or other forms of viscous materials;

[0055] S30: fix the main magnetic steel 22 on the elastic sheet 21, and fix the elastic sheet 21 on the first shell 11 or the second shell 12, and fix the coil 31 on the end surface of the first shell 11 and the second shell 12; of course, it should be pointed out here that when the main magnetic steel 22 is fixed on the elastic sheet 21, the mass block 23, the pole piece 24 and the auxiliary magnetic steel 25 in other embodiments of the present disclosure can also be fixed together, and the fixing here can be in the form of welding or bonding; when the coil 31 is fixed, the positioning flange 32 and the skeleton 33 structure mentioned above can be used to achieve fixation;

[0056] S40: buckle the first shell 11 and the second shell 12, and weld them together. After the first shell 11 and the second shell 12 are buckled together, they are fixed by the elastic sheet 21 and the viscoelastic layer 40 by applying pressure. To ensure the reliability of the connection between the two, the joints of the two are further welded and fixed by ultrasonic welding.

[0057] Those skilled in the art should understand that the present disclosure is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present disclosure. Without departing from the spirit and scope of the present disclosure, the present disclosure may be subject to various changes and improvements, which are within the scope of the present disclosure to be protected. The scope of protection claimed by the present disclosure is defined by the attached claims and their equivalents.

Claims

1. A strong vibration type linear vibration motor, characterized in that: Including housing, vibrator and stator, The shell is hollow and has two ends that are connected through it; The vibrator comprises an elastic sheet with an edge fixed in the housing, and main magnetic steels symmetrically fixed on both sides of the elastic sheet; The stator includes a coil symmetrically fixed at two ends of the housing, and the size of the coil is configured to allow the main magnetic steel to extend into the coil; Wherein, the shell includes a first shell and a second shell along its through direction, the elastic sheet is fixed on the mating surface of the first shell and the second shell, and the first shell and the second shell have a viscoelastic layer on the fixing surface facing the elastic sheet; when the two coils are synchronously passed with alternating current, the vibrator performs reciprocating linear vibration toward the two ends of the shell.

2. The strong vibration type linear vibration motor according to claim 1, characterized in that: The butt joint surfaces of the first shell and the second shell are arranged in a stepped shape, so that the outer wall of either of them extends toward the other.

3. The strong vibration type linear vibration motor according to claim 2, characterized in that: The butting surfaces of the first shell and the second shell are both provided with an annular groove, and the annular groove is used for fixing or filling the viscoelastic layer.

4. The strong vibration type linear vibration motor according to claim 3, characterized in that: The bottom of the annular groove of the first shell and / or the second shell further comprises a positioning column protruding toward the upper surface of the annular groove, and the elastic sheet comprises a positioning hole matching the positioning column.

5. The strong vibration type linear vibration motor according to claim 3, characterized in that: The viscoelastic layer is formed by filling the annular groove with soft glue.

6. The strong vibration type linear vibration motor according to claim 1, characterized in that: The elastic sheet has an arc-shaped hole inside that gradually extends toward the center, so that the elastic sheet forms a circumferential fixing portion, an elastic arm extending inward from the circumferential fixing portion, and a central fixing portion connected to the elastic arm, and the main magnetic steel is fixed on the central fixing portion.

7. The strong vibration type linear vibration motor according to claim 6, characterized in that: The vibrator also includes a mass block, a secondary magnetic steel and a pole piece; The mass block is fixed between the central fixing portion and the main magnetic steel, the auxiliary magnetic steel is fixed on the pole piece, and the pole piece is fixed on the main magnetic steel.

8. The strong vibration type linear vibration motor according to claim 3, characterized in that: The stator also includes a positioning flange and a frame. The positioning flange is fixed on the end faces of the first shell and the second shell. The positioning flange is hollow and extends inward. The frame is cylindrical and fixed on the part of the positioning flange extending inward. The coil is fixed on the frame.

9. The strong vibration type linear vibration motor according to claim 8, characterized in that: The end surfaces of the first shell and the second shell are provided with fixing grooves, the fixing grooves are provided with limiting parts, the positioning flanges are provided with limiting holes matching the limiting parts, and the viscoelastic layer is fixed in the fixing grooves for connection with the positioning flanges.

10. An assembly method of a strong vibration type linear vibration motor according to any one of claims 1 to 9, characterized in that: The following steps are involved: Laser scanning the end faces and the butt joint faces of the first shell and the second shell to increase the surface roughness; Filling a viscous material on the butt joint surface and end surface of the first shell and the second shell to form a viscoelastic layer; Fixing the main magnetic steel on the elastic sheet, fixing the elastic sheet on the first shell or the second shell, and fixing the coil on the end surfaces of the first shell and the second shell; The first shell and the second shell are buckled together and connected by welding.

Images