WO2019029054A1 - Linear vibration motor - Google Patents

Abstract

A linear vibration motor, comprising: a stator assembly, the stator assembly comprising a housing (1) having an accommodation cavity, and a magnet (2) that is disposed in the accommodation cavity and that is fixedly combined with the housing (1), the magnet (2) comprising a hollow portion (21); a vibration assembly, the vibration assembly comprising a mass block (4) as well as a coil (3) that is fixedly combined with the surface of the mass block (4) in the vibration direction of the vibration assembly, wherein because the hollow portion (21) extends along the vibrating direction of the vibration assembly, when the vibration assembly vibrates, the coil (3) vibrates along with the vibration assembly and moves into the hollow portion (21) of the magnet (2); and an elastic support member (5) configured to keep the vibration assembly suspended in the accommodation cavity of the housing (1). The described linear vibration motor structure maximizes the utilization of the magnetism of the magnet (2), increases the efficiency of the coil (3) in respect of the magnetic lines of force of the magnet (2), and increases the electromagnetic driving force of the motor. The simplicity and high degree of precision with which the motor may be assembled improves the vibration performance thereof.

Description

Linear vibration motor Technical field

The invention belongs to the technical field of electronic products. More specifically, it relates to a linear vibration motor.

Background technique

With the development of communication technologies, portable electronic devices, such as mobile phones, tablet computers, smart wearable devices, multimedia entertainment devices, etc., have become a necessity for people. In these electronic devices, a miniature linear vibration motor is usually used for feedback of the system, such as clicking the vibration feedback of the touch screen.

A linear vibration motor is a component that converts electrical energy into mechanical vibration using the principle of electromagnetic force. A conventional linear vibration motor is usually installed in a mobile communication terminal, a portable terminal or the like, which is usually installed at an edge portion of the device, and receives vibrations. The object produces vibration in a vertical direction.

Existing linear vibration motors typically include a housing having a receiving chamber in which is disposed a stator assembly, a vibrator assembly, and an elastomeric support configured to suspend the vibrator assembly within the receiving chamber. The stator assembly may be a magnet or a coil fixedly coupled to the housing, and the corresponding vibration assembly may be a coil or magnet that is supported by the elastic support for up and down vibration. The existing magnets as the stator assembly or the vibrator assembly are all cylindrical solid core structures, and the coil is surrounded by the periphery of the magnet. After the coil is energized, the coil is subjected to the ampere force to generate electromagnetic force and between the magnetic field generated by the magnet. The interaction, in turn, causes the vibrator assembly to move up and down, which in turn results in vibration of the entire linear vibration motor.

However, the existing linear vibration motor has the following drawbacks: 1. The magnetic flux utilization efficiency of the magnet is low, which affects the overall tactile sensation. 2. The existing motor assembly process is complicated, especially when the coil and the mass are assembled as vibration components, the external positioning tool needs to be used to ensure coaxial assembly, the assembly steps are cumbersome, and it is difficult to control the assembly precision. 3. The existing linear vibration motor is only suitable for vibration experience under single frequency point, and does not meet the requirements of haptic feedback application for multi-frequency point vibration.

Therefore, there is a need to provide a new type of linear vibration motor to solve the drawbacks of the prior art.

Summary of the invention

In view of the above problems, the technical problem to be solved by the present invention is to provide a linear vibration motor which can maximize the magnetic properties of the magnet, improve the utilization efficiency of the coil for the magnetic field lines of the magnet, improve the electromagnetic driving force of the motor, and the assembly process. Simple and accurate assembly, making the motor available Better vibration performance.

In order to solve the above technical problems, the present invention adopts the following technical solutions:

A linear vibration motor, the motor comprising:

a stator assembly, the stator assembly including a housing having a receiving cavity, a magnet disposed within the receiving cavity and coupled to the housing, the magnet including a hollow portion;

a vibrator assembly, the vibrator assembly including a mass, and a coil fixedly coupled to the surface of the mass along a vibration direction of the vibrator assembly; the hollow portion extending along a vibration direction of the vibrator assembly, the coil being The vibrator assembly vibrates and is inserted into the hollow portion of the magnet;

An elastic support configured to suspend the vibrator assembly within the receiving cavity of the housing.

Further, preferably, the mass includes a groove portion corresponding to the bottom of the coil and recessed inwardly from the surface of the mass, and a bottom of the coil is inserted into the groove portion to be fixed.

Further, preferably, the mass includes a convex portion corresponding to the bottom of the coil and convexly formed by a surface of the mass, the convex portion including a concave portion for inserting a bottom of the coil groove.

Furthermore, it is preferred that the mass comprises a body and a side extending upwards and/or downwards from the edge of the body.

Further, preferably, the mass includes a main portion and a side portion extending upward from an edge of the main portion, and a gap for inserting the magnet is formed between the coil and a side portion of the mass.

Further, preferably, the vibrator assembly further includes a magnetic conductive plate fixedly coupled to a lower surface of the mass, the elastic support member being fixedly coupled to a lower surface of the magnetic conductive plate and an inner side of the bottom wall of the housing Between the surfaces, and configured to suspend the vibrator assembly within the receiving cavity of the housing.

Further, it is preferable that the groove portion is a segmented structure uniformly disposed in the circumferential direction of the mass, or a continuous annular structure.

Further, it is preferable that the convex portion is a segmented structure uniformly disposed in the circumferential direction of the mass, or a continuous annular structure.

Moreover, preferably, the vibrator assembly further includes a central core secured within the coil, the central core including a body portion that is inserted within the coil.

Moreover, preferably, the central core further includes a straight portion extending outwardly from the outer surface of the side wall of the body portion and above the coil.

The beneficial effects of the present invention are as follows:

1. The linear vibration motor provided by the invention improves the structure of the magnet and its matching with the coil The method can maximize the magnetism of the magnet, improve the utilization efficiency of the coil for the magnetic field line of the magnet, and improve the electromagnetic driving force of the motor. The increase of the driving force increases the effective bandwidth of the motor, and is convenient for the dual-frequency or multi-frequency resonant frequency. The application satisfies the requirements of the vibration provided by the motor under the multi-frequency point and improves the tactile experience of the motor.

2. The linear vibration motor structure provided by the invention reduces the difficulty of the motor manufacturing process and improves the overall assembly efficiency. In particular, in the motor structure provided by the present invention, the improvement of the combination manner of the mass block and the coil, that is, the coil is directly combined and fixed on the mass block, the structure design is favorable for controlling the coaxiality between the coil and the mass block, and is convenient. The positioning of the coil relative to the position of the mass simplifies the assembly process and eliminates the need for external positioning tools.

3. In the invention, the groove portion or the convex portion provided on the mass block is used to increase the bonding strength between the coil and the mass block, thereby avoiding the low bonding strength between the coil and the mass block which occurs during the vibration process of the motor. The resulting separation of the two emerged.

4. On the other hand, the present invention further provides a center core in the coil, and the center core can further improve the utilization efficiency of the coil for the magnet line and enhance the electromagnetic driving force of the motor.

5. The linear vibration motor provided by the invention has a motor vibration balance position, and the vibrator assembly and the stator assembly are mutually attractive, which reduces the micro vibration of the motor without current or weak current, so that the motor can quickly return to a stationary state.

6. The linear vibration motor structure provided by the invention has large electromagnetic driving force and shortens the motor vibration rising time; the static balance magnetic force of the motor balance position is large, and the motor vibration falling time is shortened; the overall motor response speed is improved.

DRAWINGS

The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

Fig. 1 is a cross-sectional view showing the structure of a linear vibration motor according to a first embodiment of the present invention.

2 is a schematic view showing the arrangement of a vibrator assembly and a magnet in a linear vibration motor according to a first embodiment of the present invention.

3 is a schematic view showing the arrangement of a vibrator assembly and a magnet in a linear vibration motor according to a second embodiment of the present invention.

4 is a schematic view showing the arrangement of a vibrator assembly and a magnet in a linear vibration motor according to a third embodiment of the present invention.

Fig. 5 is a view showing the arrangement of a vibrator assembly and a magnet in a linear vibration motor according to a fourth embodiment of the present invention.

Fig. 6 is a view showing the arrangement of a vibrator assembly and a magnet in a linear vibration motor according to a fifth embodiment of the present invention.

Fig. 7 is a view showing the arrangement of a vibrator assembly and a magnet in a linear vibration motor according to a sixth embodiment of the present invention.

Detailed ways

In the following description, for the purposes of illustration However, it is apparent that these embodiments may be practiced without these specific details. In other instances, well known structures and devices are shown in block diagram form in order to facilitate describing one or more embodiments.

The "mass" used in the description of the following detailed description may also be referred to as "weights", both of which refer to one of the components that cooperate with the magnet or coil to vibrate within the motor housing as a vibrator assembly. Further, the present invention is mainly used for the improvement of the linear vibration motor used in the description, and may also be referred to as a Y-direction vibration motor. However, for convenience of description, in the following description of the embodiments, a linear vibration motor will be specifically described as an example.

In order to explain the present invention more clearly, the present invention will be further described in conjunction with the preferred embodiments and the accompanying drawings. It should be noted that, for ease of understanding, the descriptions of the "upper surface", "lower surface", "bottom", "top" and the like referred to in the present invention are merely illustrative of the styles provided with reference to the drawings, which are not used. To the extent that it is understood by those skilled in the art, when the position of the motor is changed in the present invention, the corresponding description and terminology referred to herein should be based on its actual effect in the motor.

The invention provides a linear vibration motor with a novel structure. Firstly, the vibration motor improves the structure of the magnet and the arrangement of the coil, and effectively solves the problem that the magnetic line utilization efficiency of the current magnet is low, and the existing linear vibration motor is only applicable. The vibration experience at a single frequency point does not satisfy the requirements for haptic feedback applications for multi-frequency point vibration. Secondly, the linear vibration motor structure provided by the invention is also specially improved for the structure of the vibrator assembly in the motor, which reduces the difficulty of the motor manufacturing process and improves the overall assembly efficiency.

Specifically, referring to FIGS. 1 and 2, a linear vibration motor includes: a stator assembly, a vibrator assembly, and an elastic support member 5; wherein the stator assembly includes a housing 1 having a receiving cavity, a magnet 2 accommodating and fixed in combination with the housing 1 , the magnet 2 including a hollow portion 21 extending in a vibration direction of the vibrator assembly; in the illustrated embodiment, the housing of the present invention 1 includes a first housing 11 having an opening at the bottom, and a second housing 12 fixedly coupled to the opening; the first housing 11 and the second housing 12 constitute a housing 1 having a receiving cavity. In addition, the magnet 2 in the present invention may be a segmented or continuous annular structure, which is not limited in the present invention.

The vibrator assembly of the present invention comprises a mass 4 fixed to the upper surface of the magnetic conductive plate 6, and along the vibration The vibration direction of the sub-assembly is combined with the coil 3 fixed on the upper surface of the mass 4; in the present invention, the length direction of the coil 3 extends along the vibration direction of the vibrator assembly, and the mass 4 is mainly disposed in a direction perpendicular to the vibration direction of the vibrator assembly, and the coil 3 The combination is fixed to the upper surface of the mass 4, and when the vibrator assembly vibrates, the coil 3 vibrates with the vibrator assembly and is inserted into the hollow portion 21 of the magnet 2. In the present invention, the vibrator assembly is mainly composed of a mass 4 fixed on the magnetic conductive plate 6 and a coil 3 fixed on the mass. Since the coil 3 is directly bonded and fixed to the upper surface of the mass 4, it is assembled during the motor assembly. It facilitates the control of the coaxiality between the coil 3 and the mass 4, and facilitates the positioning and installation of the coil 3 relative to the position of the mass 4, which simplifies the assembly process and eliminates the external positioning tooling.

Corresponding to the magnetic conductive plate 6, the elastic support member 5 of the present invention is fixedly fixed between the lower surface of the magnetic conductive plate 6 and the inner side surface of the second casing 12, and is configured to suspend the vibrator assembly In the housing cavity of the housing 1. It should be noted that when the magnetic conductive plate is not disposed in the motor, the upper end of the elastic support member may be directly fixed and fixed with the lower surface of the mass. The illustrated embodiment is only a preferred embodiment, and is not used for The motor structure provided by the present invention is limited. In addition, as another modified embodiment, the magnetic conductive plate may also be combined and fixed on the upper surface of the illustrated mass, and the magnetic conductive plate includes a notch fixed to the upper surface of the mass, and the elastic support is combined. Fixed between the lower surface of the mass and the inner side surface of the second housing, the structural configuration of the deformed mass and the magnetically permeable plate has advantages over the prior art of the motor structure provided by the present invention The advantages are the same and will not be described here.

Further preferably, in the present invention, the first housing 11 and the second housing 12 can both be made of a material having magnetic permeability, so that the magnetic lines of force of the magnet can be closed, and the magnetic action of the magnet 2 can be maximized to enhance the electromagnetic of the motor. Driving force. As a specific embodiment of the present invention, the structure of the casing 1 shown in FIG. 1 has a circular structure, and it is obvious that the casing may also have a non-circular cross-section structure, for example, a rectangular parallelepiped shape and a rounded rectangular shape. Wait. In the present invention, the magnet 2 having an annular structure fixed in combination with the inner surface of the top wall of the first casing 11 is used as a stator assembly, and the coil 3 is inserted as a part of the vibrator assembly into the hollow portion 21 of the magnet 2 with the vibrator assembly. The magnet 2 as a stator having a ring structure and its arrangement with the coil 3 as a vibrator are compared with the columnar solid core magnet used in the conventional vibration motor, due to the magnetic field lines of the existing cylindrical solid magnet. The radiation is dispersed outward from the central axis, and the magnetic lines of the ring-shaped structural magnet of the present invention are concentrated on the central axis, so that the magnetic field strength of the coil disposed on the central axis of the magnet of the annular structure is higher than that of the magnetic field. The coil of the periphery of the cylindrical solid core magnet; and the coil of the present invention is disposed in the inner space of the magnet having the annular structure, and the diameter of the coil can be made smaller, so the effective number of turns of the coil is significantly higher than that of the outer core of the cylindrical solid magnet. The effective number of turns of the large-diameter coil, and the linear vibration motor provided by the present invention can maximize the magnetism of the magnet and increase the magnetic field line of the coil for the magnet Efficiency and enhance the horse The electromagnetic driving force, and the increase of the driving force, the effective bandwidth of the motor is increased, which is convenient for the application of the dual-frequency or multi-frequency resonant frequency, and meets the requirements of the vibration provided by the motor under the multi-frequency point, thereby improving the motor. The tactile experience and overall improved the overall performance of the linear vibration motor.

Further, the linear vibration motor of the present embodiment further includes a circuit 3 for electrically connecting the coil 3 to an external device; the printed circuit board 8 includes: a lower surface of the magnetic conductive plate 6 And a fixing portion 81 electrically connected to the coil 3; a connecting portion 82 located outside the casing 1 and fixedly coupled to the upper surface of the second casing 12 for electrically connecting with an external device; The fixing portion 81 and the connecting portion 82 are connected to a flexible connecting portion 83 of a unitary structure. The flexible connecting portion 83 is located below the elastic arm of the elastic support member 5. When the vibrator assembly is vibrated, when the elastic arm is pressed or deformed, the flexible connecting portion 83 moves up and down, thereby avoiding the flexible connecting portion 83 and the elastic portion. Collisions between the arms affect the vibration performance of the vibration motor. When the elastic arm is deformed to the extreme position by pressure, the limit of the damping member provided on the upper surface of the second casing can be prevented to prevent the elastic arm from being pressed to the flexible connecting portion to damage the flexible connecting portion. It will be understood by those skilled in the art that the mass and/or the magnetic conductive plate in the motor should be provided with wire vias connecting the coil and the printed circuit board to enable the coil to be electrically connected to the external device, but for the via hole. The specific position and structural form are not limited by the present invention.

In addition, in the present invention, the magnetic conductive plate 6 is disposed under the magnet 2, so that the stator assembly including the magnet 2 has a large attraction force to the vibrator assembly, and the attractive force can provide a certain component to the vibrator assembly after the motor is powered off. The vibration resistance, in simple terms, is equivalent to providing a brake to the vibrator assembly, which enables the vibrator assembly in the motor to quickly stop vibrating, ie "shortening the motor vibration drop time". Further, since the center core can be included in the coil, the utilization of the magnetic field lines of the magnet is increased, so that the electromagnetic driving force of the motor is increased, thereby accelerating the starting process of the motor, that is, "shortening the motor vibration rise time". Furthermore, the linear vibration motor provided by the present invention has an advantage over the prior art in that when the motor is in the vibration balance position, the vibrator assembly and the stator assembly are mutually attractive, and the micro vibration of the motor without current or weak current can be reduced. , so that the motor can quickly return to a standstill. Moreover, the linear vibration motor structure provided by the present invention has a large electromagnetic driving force, which can shorten the motor vibration rise time; and since the motor is in a balanced position, the static magnetic force is large, and the motor vibration fall time can be further shortened, so that the present invention can improve the motor as a whole. responding speed.

In order to further increase the bonding strength between the coil 3 and the mass 4, the occurrence of separation between the two due to the low bonding strength of the coil 3 and the mass 4 occurring during the vibration of the motor is avoided. Referring to Fig. 3, for the combined fixing structure between the coil 3 and the mass 4, Fig. 3 is a schematic view showing the arrangement of the vibrator assembly and the magnet in the linear vibration motor according to the second embodiment of the present invention. The mass 4 includes a recessed inwardly from the upper surface of the mass 4 corresponding to the bottom of the coil 3 The groove portion 41 is formed such that the bottom of the coil 3 is inserted into the groove portion 41 to be fixed. The design of the groove portion 41 can increase the joint fixing area between the coil 3 and the mass 4, thereby increasing the fixing strength between the two. Further preferably, the groove portion 41 may be a segmented structure uniformly disposed circumferentially along the mass 4 under the condition of ensuring vibration stability of the vibration component, or the groove portion 41 is a continuous ring shape. The structure is not limited by the present invention.

In addition, with respect to the combined fixing structure between the coil 3 and the mass 4, different from the second embodiment, referring to FIG. 4, FIG. 4 shows the configuration of the vibrator assembly and the magnet in the linear vibration motor according to the third embodiment of the present invention. Schematic. The mass 4 includes a protrusion 42 corresponding to the bottom of the coil 3 and convexly formed by the upper surface of the mass 4, the protrusion 42 including a concave for inserting the bottom of the coil 3 groove. The convex portion 42 cooperates with the groove design on the convex portion, and the joint fixing area between the coil 3 and the mass 4 can also be increased, thereby increasing the fixing strength between the two. Further preferably, the convex portion 42 may be a segmented structure uniformly disposed along the circumferential direction of the mass, or the convex portion 42 may be a continuous annular structure under the condition of ensuring vibration stability of the vibration assembly. The invention is not limited thereto.

As a modification of the intermediate mass structure of the first embodiment, in the present invention, the mass 4 may include not only the portion 43 disposed in a direction perpendicular to the vibration direction of the vibrator assembly but also the edge of the portion 43 up and down. Or a side portion 44 that extends downward. By the arrangement of the side portions 44, the mass of the mass 4 can be increased, the vibration amplitude of the vibration assembly can be increased, and the purpose of increasing the vibration of the motor can be achieved. Specifically, in order to avoid collision effects between the mass 4 and the second housing 12 or the elastic support 5, preferably, referring to FIG. 5, the vibrator assembly and the magnet of the first embodiment shown in FIGS. The arrangement structure, as a further modified fourth embodiment, the mass 4 includes a main portion 43 and a side portion 44 extending upward from the edge of the main portion 43, and the coil 3 is formed with the side portion 44 of the mass 4 for The gap 7 into which the magnet 2 is inserted.

Referring to FIG. 6 , the arrangement structure of the vibrator assembly and the magnet of the fourth embodiment shown in FIG. 5 is further improved. In the embodiment, the vibrator assembly further includes a fixing to the coil 3 . The center core 9, the center core 9 includes a body portion 91 that is inserted into the coil 3. The central core 9 can provide a guiding path and a direction for the magnetic lines of the magnet 2, and the central core 9 can be made of a magnetic material having a strong magnetic permeability, and has a high magnetic permeability, which is convenient for guiding the magnetic lines, and is concentrated toward the coil 3, and In the energized coil, a large magnetic induction intensity can be generated, which is advantageous for reducing the volume of the coil. The other advantages of the sixth embodiment are the same as those of the motor provided by the fifth embodiment described above, and are not described herein again.

Referring to FIG. 7, the configuration of the vibrator assembly and the magnet of the sixth embodiment shown in FIG. 6 is further improved. In the embodiment, the center core 9 further includes The flat portion 92 of the outer surface of the side wall of the body portion 92 extends outwardly and is located above the coil 3. The flat portion 92 is integral with the body portion 91. The straight portion 92 can be used to provide a guiding path and direction for the magnetic lines of force, so that the magnetic lines of force are concentrated at the coil 3 to increase the strength of the magnetic field at the position where the coil 3 is located. Further, the circumferential outer edge of the straight portion 92 may be located inside, outside or flush with the circumferential outer edge of the coil 3. In the case where the interference between the straight portion 92 and the magnet 2 is ensured, preferably, the circumferential outer edge of the straight portion 92 is located outside the circumferential outer edge of the coil 3, making it as possible as possible Provide guidance for magnetic lines of force. In addition, between the outer wall surface of the body portion 91 and the inner wall surface of the coil 3, between the lower surface of the flat portion 92 and the top upper surface of the coil 3 between the center core 9 and the coil 3 is ensured. Under the condition of relative insulation, a gap may be left or the two may be fixedly attached. However, in order to facilitate the coaxial and accurate assembly between the central core and the coil, and to simplify the machining process and assembly difficulty of the central core, it is preferable that the outer wall surface of the body portion 91 and the inner wall surface of the coil 3 are straight. A gap is left between the lower surface of the portion 92 and the top upper surface of the coil 3. The other advantages of the seventh embodiment are the same as those of the motor provided by the sixth embodiment described above, and are not described herein again.

In summary, the linear vibration motor structure provided by the present invention can maximize the magnetic properties of the magnet, improve the utilization efficiency of the coil for the magnetic field lines of the magnet, and improve the electromagnetic driving force of the motor. In addition, the motor structure provided by the invention also simplifies the assembly process of the vibrator assembly, in particular, the method for combining the mass and the coil is improved, the coil is directly fixed and fixed on the mass, and for the combination between the two, The invention also utilizes the groove portion or the convex portion provided on the mass block to increase the bonding strength between the coil and the mass block, thereby avoiding the occurrence of a low bonding strength between the coil and the mass block caused by the motor during the vibration process. The emergence of the separation of the two.

It is apparent that the above-described embodiments of the present invention are merely illustrative of the present invention and are not intended to limit the embodiments of the present invention, and those skilled in the art can also make the above description. It is to be understood that various changes and modifications may be made without departing from the spirit and scope of the invention.

Claims (10)

A linear vibration motor, characterized in that the motor comprises: a stator assembly, the stator assembly including a housing having a receiving cavity, a magnet disposed within the receiving cavity and coupled to the housing, the magnet including a hollow portion; a vibrator assembly, the vibrator assembly including a mass, and a coil fixedly coupled to the surface of the mass along a vibration direction of the vibrator assembly; the hollow portion extending along a vibration direction of the vibrator assembly, the coil being The vibrator assembly vibrates and is inserted into the hollow portion of the magnet; An elastic support configured to suspend the vibrator assembly within the receiving cavity of the housing. A linear vibration motor according to claim 1, wherein said mass includes a groove portion corresponding to a bottom portion of said coil and recessed inwardly from a surface of said mass, and a bottom portion of said coil is inserted into said concave portion. The groove is fixed inside. A linear vibration motor according to claim 1, wherein said mass includes a convex portion corresponding to a bottom portion of said coil and convexly formed by a surface of said mass, said convex portion including a supply portion The bottom of the coil is inserted into a fixed groove. The linear vibration motor of claim 1 wherein said mass comprises a body portion and a side portion extending upwardly and/or downwardly from an edge of the body portion. The linear vibration motor according to claim 1, wherein the mass includes a main portion and a side portion extending upward from an edge of the main portion, and a gap for inserting the magnet is formed between the coil and a side portion of the mass. A linear vibration motor according to claim 1, wherein said vibrator assembly further comprises a magnetically permeable plate fixedly coupled to a lower surface of said mass, said elastic support being fixedly coupled under said magnetically permeable plate The surface is interposed between the inner side surface of the bottom wall of the housing and is configured to suspend the vibrator assembly within the receiving cavity of the housing. The linear vibration motor according to claim 2, wherein the groove portion is a segmented structure uniformly disposed in the circumferential direction of the mass, or is a continuous annular structure. The linear vibration motor according to claim 3, wherein the convex portion is a segmented structure uniformly disposed in the circumferential direction of the mass, or is a continuous annular structure. The linear vibration motor of claim 1 wherein said vibrator assembly further comprises a central core secured within said coil, said central core including a body portion inserted within said coil. A linear vibration motor according to claim 9, wherein said center core further comprises a straight portion extending outward from said outer surface of said body portion and located above said coil unit.

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