JP7441533B2 - linear vibration actuator - Google Patents

Description

The present invention relates to a linear vibration actuator.

Generally, a mobile terminal such as a smartphone is sometimes equipped with a vibration generator to transmit vibrations to the user. The movable element provided in the vibration generator vibrates with a predetermined vibration center by not only applying a driving force but also applying an urging force from both sides in the vibration direction. As a vibrating device for vibrating the movable element in this manner, a linear vibrating apparatus that applies an urging force to the movable element using a magnet has been proposed (see, for example, Patent Document 1). In the linear vibration device described in Patent Document 1, a magnet is provided in each of the movable element and the housing, and the movable element is biased by a magnetic spring.

US Patent Application Publication No. 2016/0226359

However, in the configuration in which the movable element is biased by a magnetic spring as described in Patent Document 1, the spring constant of the magnetic spring has nonlinearity (the spring constant changes depending on the position of the movable element). The resonant frequency changes depending on the position, and when trying to obtain a large amplitude through resonance, control of the drive current becomes complicated.

At this time, the closer the magnets are to each other, the greater the change in the spring constant (higher nonlinearity), so use a region where the magnets are relatively far apart and the change in the spring constant is small (low nonlinearity). A possible configuration is possible. However, in a region with low nonlinearity, the absolute value of the spring constant is small, and a desired acceleration may not be obtained when driving the movable element.

An object of the present invention is to provide a linear vibration actuator that can obtain a large acceleration while being easy to control.

The linear vibration actuator of the present invention includes a movable element capable of rectilinear vibration in a predetermined vibration direction, a housing means for accommodating the movable element, a driving means for driving the movable element having a coil and a magnet, and a movable element for driving the movable element. a biasing means that applies a biasing force to the child from both sides in the vibration direction, the biasing means includes a spring member that applies the biasing force by being elastically deformed, and a magnet of the driving means. is characterized in that it has a magnetic biasing means configured separately and applying the biasing force by repulsive force between magnets fixed to each of the movable element and the housing means.

According to the present invention as described above, since the biasing means includes the spring member and the magnetic biasing means, the spring constant of the biasing means is equal to the linear spring constant of the spring member and the nonlinear spring constant of the magnetic biasing means. It is the sum of the spring constant and Therefore, even if a low nonlinearity region of the spring constant of the magnetic biasing means is used, the total spring constant can be ensured, and a large acceleration can be obtained. Furthermore, the nonlinearity of the total spring constant can be reduced, and the driving means can be easily controlled.

Moreover, in the linear vibration actuator of the present invention, it is preferable that the spring member is provided so as to be elastically deformed over the entire length of the stroke of the movable element. According to such a configuration, the total spring constant can be increased over the entire length of the stroke of the movable element.

Moreover, in the linear vibration actuator of the present invention, the spring member may be provided so as to be elastically deformed during a part of the stroke of the movable element. According to such a configuration, when the movable element moves away from the center of vibration, a large biasing force is applied, and a large acceleration can be obtained. Although the total spring constant changes discontinuously at the deformation start position of the spring member, only the linear spring constant increases, and control of the driving means is less likely to become complicated.

Further, the linear vibration actuator of the present invention further includes a guide means that extends in a rod shape along the vibration direction and guides the movable element, and the spring member is formed in a coil shape, and the guide means is formed in a coil shape. Preferably, it is inserted. According to such a configuration, the space for providing the spring member can be reduced, and the enlargement of the entire device can be suppressed.

Further, in the linear vibration actuator of the present invention, the magnet of the driving means generates a driving force by having a magnetic pole direction substantially perpendicular to the vibration direction, and the magnetic biasing means has a magnetic pole direction substantially perpendicular to the vibration direction. It is preferable to apply the biasing force by having a structure along the following lines. According to such a configuration, a large magnetic force can be generated in each of the driving means and the magnetic biasing means.

According to the linear vibration actuator of the present invention, since the biasing means includes the spring member and the magnetic biasing means, it is possible to obtain a large acceleration while facilitating control.

FIG. 1 is an exploded perspective view showing a linear vibration actuator according to a first embodiment of the present invention. FIG. 3 is a perspective view showing the linear vibration actuator. It is a side view which shows typically the magnet which comprises the drive means of the said linear vibration actuator. FIG. 3 is a plan view schematically showing magnetic biasing means of the linear vibration actuator. It is a graph schematically showing the relationship between the displacement of the movable element and the spring constant of the biasing means in the linear vibration actuator. It is a graph which shows typically the relationship between the frequency in the said linear vibration actuator, and the acceleration of the said mover. FIG. 2 is an exploded perspective view showing a linear vibration actuator according to a second embodiment of the present invention. FIG. 3 is a perspective view showing the linear vibration actuator. It is a graph schematically showing the relationship between the displacement of the movable element and the spring constant of the biasing means in the linear vibration actuator.

Hereinafter, each embodiment of the present invention will be described based on the drawings. In the second embodiment, the same constituent members and constituent members having similar functions as the constituent members described in the first embodiment are given the same reference numerals as those in the first embodiment, and the explanation thereof will be omitted.

[First embodiment]
As shown in FIG. 1, the linear vibration actuator 1A of this embodiment includes a movable element 2, two shafts 3A and 3B, a coil 4, a case 5 as a housing means, two fixed side magnets 6A, 6B, a flexible printed circuit board (FPC) 7, and four coil springs 8, and is mounted on a mobile terminal such as a smartphone to generate vibration. The linear vibration actuator 1A is formed in the shape of a rectangular parallelepiped whose longitudinal direction is the vibration direction of the movable element 2. Hereinafter, the vibration direction is the X direction, the width direction is the Y direction, and the height direction is the Z direction.

As shown in FIG. 2, the mover 2 includes a frame 21, driving magnets 22A to 22C, a yoke 23, and two moving side magnets 24A and 24B.

The frame body 21 is formed into a rectangular plate shape along the XY plane with its longitudinal direction in the X direction, and has a rectangular parallelepiped-shaped accommodating portion 211 . The frame body 21 has, at its four corners, holding portions 212 having a circular cross section and opening in the Y direction.

The driving magnets 22A to 22C are arranged in the X direction and housed in the housing portion 211 of the frame body 21. At this time, the driving magnets 22A to 22C are arranged with the magnetization directions in a Halbach array as shown in FIG. That is, the N pole of the drive magnet 22A is directed upward in the Z direction (opposite to the coil 4), the N pole of the drive magnet 22B is directed toward the drive magnet 22A side in the X direction, and the N pole of the drive magnet 22C is directed toward the drive magnet 22A side in the X direction. The N pole is directed downward in the Z direction. In this way, the magnetic pole directions of the drive magnets 22A and 22C are along the Z direction.

With such a Halbach arrangement, magnetic flux upward in the Z direction is concentrated above the drive magnet 22A, and magnetic flux downward in the Z direction is concentrated above the drive magnet 22C. Note that the number of drive magnets and the magnetization direction are not limited to those described above, and any structure may be used as long as a Lorentz force is generated in the X direction when current is passed through the coil.

The yoke 23 is formed of a ferromagnetic material such as iron into a rectangular plate shape along the XY plane, and is fixed to the upper side of the frame 21 in the Z direction. The weight of the movable element 2 as a whole may be adjusted by adjusting the weight of the yoke 23 (that is, the yoke 23 may be used as a weight), or the yoke may be omitted.

The two moving side magnets 24A and 24B are composed of samarium cobalt magnets, and are arranged at both ends in the X direction, respectively.

The shafts 3A and 3B are rod-shaped members with a circular cross section that extend along the X direction, and are configured separately from the case 5. Two shafts 3A and 3B are arranged to sandwich the movable element 2 from the Y direction.

Four holding parts 212 of the mover 2 slidably hold the shafts 3A and 3B. That is, the shafts 3A and 3B are positioned inside the holding part 212 formed in a cylindrical shape (inserted through the holding part 212). Since the holding portion 212 of the movable element 2 slidably holds the shafts 3A and 3B on both sides in the Y direction, the movable element 2 is guided to move in the X direction by the shafts 3A and 3B. In this way, the shafts 3A and 3B function as guide means.

The coil 4 is arranged on a flexible printed circuit board (FPC) 7. The FPC 7 is formed into a plate shape along the XY plane, is immovably fixed to the case 5, and has a power supply section 71 that protrudes outside the case 5 and is supplied with power.

The movable element 2 is arranged to face the coil 4 in the Z direction. The coil 4 has a substantially rectangular shape and includes a pair of first extending portions 41 and 42 extending along the X direction and a pair of second extending portions 43 and 44 extending along the Y direction. It is formed in the shape of The pair of first extending portions 41 and 42 are arranged on both sides of the driving magnets 22A to 22C in the Y direction when viewed from the Z direction. Further, when viewed from the Z direction, the second extending portion 43 is arranged to overlap the driving magnet 22A, and the second extending portion 44 is arranged to overlap the driving magnet 22C.

When power is supplied to the coil 4, the interaction between the current flowing through the second extension parts 43 and 44 and the magnetic field in the vicinity thereof (around the driving magnets 22A and 22C) causes a Lorentzian shift along the X direction. Force arises. As a result, a driving force along the X direction is applied to the movable element 2. That is, the coil 4 and the driving magnets 22A to 22C function as a driving means for driving the movable element 2.

Incidentally, when the movable element 2 moves in the X direction, a large Lorentz force is obtained in a range where the second extension parts 43 and 44 and the driving magnets 22A and 22C overlap when viewed from the Z direction. Therefore, the stroke length of the movable element 2 changes depending on the positional relationship between the second extending parts 43 and 44 and the driving magnets 22A and 22C.

The case 5 includes a frame-shaped case body 51, a lower lid 52 that extends along the XY plane and closes the lower opening of the case body 51, and an upper lid 53 that extends along the XY plane and closes the upper opening of the case body 51. , and is formed in a rectangular parallelepiped shape with the longitudinal direction in the X direction. The case 5 houses the movable element 2, the shafts 3A and 3B, the coil 4, the stationary side magnets 6A and 6B, and the FPC 7.

Holding holes 510 are formed in walls 511 and 512 on both sides in the X direction of the case body 51, into which the ends of the shafts 3A and 3B are inserted. Thereby, the shafts 3A and 3B are supported by the case 5 so as to extend along the X direction.

The fixed side magnet 6A is made of a samarium cobalt magnet, and is fixed between the two holding holes 510 in the wall 511 of the case body 51 and on the inner surface side. Furthermore, the fixed side magnet 6B is fixed between the two holding holes 510 in the wall 512 of the case body 51 and on the inner surface side. In this embodiment, the stationary magnets 6A, 6B and the movable magnets 24A, 24B are made of samarium cobalt magnets that have excellent heat resistance, corrosion resistance, etc., but other types of magnets may also be used.

The shafts 3A and 3B are inserted through the coil springs 8, and the four coil springs 8 are arranged at both ends of the two shafts 3A and 3B. Each coil spring 8 is arranged between the movable element 2 and the walls 511 and 512 of the case body 51. In this embodiment, one end of the coil spring 8 is fixed to the mover 2 and the other end is fixed to the walls 511 and 512, and the coil spring 8 is elastically deformed over the entire length of the stroke of the mover 2. It is provided. Note that only one end of the coil spring 8 may be fixed, or both ends may not be fixed. Further, when the movable element 2 is located at the vibration center in the X direction, the coil spring 8 may be somewhat compressed or may be in a natural state.

When the movable element 2 approaches the wall 511 side from the vibration center, the coil spring 8 disposed between the movable element 2 and the wall 511 is compressed and elastically deformed, causing the movable element 2 to be attached to the wall 512 side. Give power. On the other hand, when the movable element 2 approaches the wall 512 side from the vibration center, the coil spring 8 disposed between the movable element 2 and the wall 512 is compressed and elastically deformed, and moves toward the wall 511 side with respect to the movable element 2. imparts a biasing force. In this way, the four coil springs 8 function as spring members that apply biasing force to the movable element 2 from both sides in the X direction by being mechanically compressed and elastically deformed. Note that the coil spring 8 may apply an urging force to the movable element 2 by being stretched and elastically deformed.

Next, detailed structures of the moving side magnets 24A, 24B and the fixed side magnets 6A, 6B will be described with reference to FIG. 4. In addition, the moving side magnet 24A and the moving side magnet 24B have the same structure, and the fixed side magnet 6A and the fixed side magnet 6B have the same structure. Therefore, the configurations of the moving magnet 24A and the fixed magnet 6A will be described below, and the explanation of the moving magnet 24B and the fixed magnet 6B will be omitted.

The entire moving side magnet 24A is formed into a rectangular parallelepiped shape with each side along the X direction, Y direction, and Z direction, and has a first magnetic section A1 and a second magnetic section A2 that are magnetically divided in the Y direction. and has. That is, the division plane between the first magnetic section A1 and the second magnetic section A2 is along the ZX plane.

In the first magnetic section A1, the N pole faces inward (toward the drive magnets 22A to 22C), and the S pole faces to the outside (to the fixed magnet 6A side). On the other hand, in the second magnetic section A2, the N pole faces outward and the S pole faces inward. That is, the magnetic poles of the first magnetic section A1 and the second magnetic section A2 that are adjacent to each other in the Y direction are opposite to each other. Note that the first magnetic section A1 and the second magnetic section A2 may be formed by combining two physically separated magnets, or the magnetized region may be divided when magnetizing one member. The first magnetic section A1 and the second magnetic section A2 may be formed by. In this way, the magnetic pole direction of the moving magnet 24A is along the X direction in both the first magnetic section A1 and the second magnetic section A2.

The entire fixed side magnet 6A is formed in the shape of a rectangular parallelepiped with each side along the X direction, the Y direction, and the Z direction, and has a first magnetic section B1 and a second magnetic section B2 that are magnetically divided in the Y direction. and has. That is, the division plane between the first magnetic section B1 and the second magnetic section B2 is along the ZX plane.

In the first magnetic section B1, the N pole faces outside (toward the wall 511), and the S pole faces inside (towards the moving magnet 24A). On the other hand, in the second magnetic section B2, the north pole faces inward and the south pole faces outside. That is, the magnetic poles of the first magnetic section B1 and the second magnetic section B2 that are adjacent to each other in the Y direction are opposite to each other. Note that the first magnetic section B1 and the second magnetic section B2 may be formed by combining two physically separated magnets, or the magnetized region may be divided when magnetizing one member. The first magnetic section B1 and the second magnetic section B2 may be formed by. In this way, the magnetic pole direction of the fixed magnet 6A is along the X direction in both the first magnetic section B1 and the second magnetic section B2.

The first magnetic section A1 of the moving magnet 24A and the first magnetic section B1 of the fixed magnet 6A face each other in the X direction, and the second magnetic section A2 of the moving magnet 24A and the second magnetic section B2 of the fixed magnet 6A face each other in the X direction. are opposed in the X direction. That is, the movable side magnet 24A and the fixed side magnet 6A have the same polarity facing each other, so that a repulsive force is generated. In this way, the movable magnet 24A and the fixed magnet 6A apply a biasing force to the mover from one side in the X direction by repulsive force. Therefore, the movable side magnets 24A, 24B and the stationary side magnets 6A, 6B function as magnetic biasing means that applies biasing force to the movable element 2 from both sides in the X direction.

The coil spring 8 as a spring member that applies a biasing force as described above, and the movable side magnets 24A, 24B and fixed side magnets 6A, 6B as magnetic biasing means constitute biasing means. The spring constant of such a biasing means will be explained with reference to FIG. 5, which is a schematic graph. In FIG. 5, the horizontal axis represents the displacement (position) of the movable element 2, and the vertical axis represents the spring constant. Further, when the movable element 2 is located at the center position, the displacement is set to 0.

The spring constant of the spring member remains constant regardless of the displacement of the movable element 2, as shown by the dashed line. On the other hand, the spring constant of the magnetic biasing means changes depending on the displacement of the movable element 2, as shown by the broken line. The Coulomb force of the magnetic biasing means is inversely proportional to the square of the difference between the gap between the magnetic biasing means at the center position of the movable element 2 and the displacement of the movable element 2. The spring constant is a value obtained by differentiating the Coulomb force, and has a linear term and a nonlinear term. That is, as shown by the broken line, the spring constant of the magnetic biasing means has a relatively small change and low nonlinearity when the mover 2 is located within a predetermined range from the center position, but when it is outside the predetermined range from the center position, Nonlinearity becomes high when the position is located at .

In this embodiment, the range where the spring constant is within 1.1 times the spring constant of the magnetic biasing means at the center position is defined as a low nonlinearity region, and the range where the spring constant is greater than 1.1 times is defined as a high nonlinearity region. It is considered a sexual area. The stroke of the movable element 2 is set so that the movable element 2 vibrates within a low nonlinearity region. Further, the ratio of the spring constant of the spring member to the spring constant of the magnetic biasing means is preferably 1:0.2 to 0.5 at the center position, and the ratio is preferably 1:0.2 to 0.5 at the boundary between the low nonlinearity region and the high nonlinearity region. The ratio is preferably 1:0.7 to 1.

The spring constant of the biasing means is the sum of the spring constant of the spring member and the spring constant of the magnetic biasing means, as shown by the solid line. Since the spring constant of the spring member is constant, the curve representing the spring constant of the biasing means is obtained by translating the curve representing the spring constant of the magnetic biasing means upward. Therefore, within the low nonlinearity region, the nonlinearity of the spring constant of the biasing means is also kept low.

When starting to drive the movable element 2 in the linear vibration actuator 1A as described above, the movable element 2 is moved back and forth so that the amplitude of the movable element 2 gradually increases by frequency sweeping the drive current. Similarly, when stopping the drive of the movable element 2, the movable element 2 is moved back and forth so that the amplitude of the movable element 2 gradually decreases by frequency sweeping the drive current. In this way, a transition time is required for the movable element 2 to reach a predetermined acceleration or for the acceleration to reach zero. At this time, the higher the nonlinearity of the spring constant of the biasing means, the more likely it is that beats will occur and the transition time will be longer.

FIG. 6 schematically shows the relationship between the frequency at which the movable element 2 is driven (the frequency of the drive current) and the acceleration of the movable element 2. The acceleration of the movable element 2 gradually increases as the frequency increases, reaches a maximum value at a predetermined frequency, and then rapidly decreases as the frequency increases. At this time, a frequency slightly lower than the frequency at which the maximum value occurs is set as the rating point. That is, below the frequency of the rated point, the displacement of the movable element 2 is maintained within the low nonlinearity region. Moreover, the overdrive frequency ranges from the rated point to the maximum frequency.

According to this embodiment, the following effects are achieved. That is, since the biasing means includes the spring member and the magnetic biasing means, the spring constant of the biasing means can be ensured even when a low nonlinearity region is used, and a large acceleration can be obtained. Moreover, the nonlinearity of the spring constant of the biasing means can be reduced, and the control when supplying electric power to the coil 4 can be made easier.

In addition, by securing the spring constant of the biasing means while using the low nonlinearity region as described above, there is no need to increase the magnet of the biasing means in order to increase the spring constant, and the low nonlinearity region can be maintained. There is no need to increase the spacing between the magnets of the magnetic biasing means for magnification. Thereby, the entire linear vibration actuator 1A can be downsized.

Further, by using the low nonlinearity region, the transition time when the vibration of the movable element 2 starts or stops can be shortened.

Further, by using the low nonlinearity region, the frequency rating point of the movable element 2 is set lower than the frequency at which the acceleration is maximum. Thereby, when a large acceleration is required, the movable element 2 can be driven at the overdrive frequency (using the highly nonlinear region).

Further, since the coil spring 8 is elastically deformed over the entire length of the stroke of the movable element 2, the spring constant of the biasing means can be increased over the entire length of the stroke of the movable element 2.

Further, by inserting the shafts 3A and 3B through the coil spring 8, the space for providing the coil spring 8 can be reduced, and the overall size of the linear vibration actuator 1 can be suppressed.

Furthermore, the magnetic pole directions of the driving magnets 22A and 22C constituting the driving means are substantially orthogonal to the X direction which is the vibration direction, and the moving side magnets 24A and 24B and the fixed side magnet 6A constituting the magnetic biasing means. , 6B are along the X direction, which is the vibration direction, so that a large magnetic force can be generated in each of the driving means and the magnetic biasing means.

[Second embodiment]
The linear vibration actuator 1B of this embodiment is obtained by replacing the coil spring 8 of the linear vibration actuator 1A of the first embodiment with a coil spring 9, as shown in FIGS. 7 and 8.

The coil spring 9 has approximately half the length of the coil spring 8, and one end thereof is not fixed to the movable element 2, and the other end is fixed to the walls 511 and 512. Note that the coil spring 9 may have a configuration in which one end is fixed to the movable element 2 and the other end is not fixed to the walls 511 and 512, or a configuration in which both ends are not fixed.

Since the coil spring 9 has the above dimensions, the coil spring 9 is not compressed and does not deform when the movable element 2 is located at the center of vibration. When the movable element 2 moves approximately half of its stroke from the center of vibration toward the wall 511, the movable element 2 and the coil spring 9 come into contact, and the coil spring 9 begins to be compressed, thereby applying a biasing force. When the movable element 2 moves approximately half the stroke toward the wall 512 from the most compressed state of the coil spring 9, the coil spring 9 returns to its natural state and no biasing force is applied.

When the movable element 2 moves approximately half of its stroke from the center of vibration toward the wall 512, the movable element 2 and the coil spring 9 come into contact, and the coil spring 9 begins to be compressed, thereby applying a biasing force. When the movable element 2 moves approximately half the stroke toward the wall 511 from the most compressed state of the coil spring 9, the coil spring 9 returns to its natural state and no biasing force is applied. In this way, the coil spring 9 is elastically deformed during a portion of the stroke of the movable element 2.

Although the mechanical spring constant of the coil spring 9 is constant, the effective spring constant, which takes actual deformation into consideration, is 0 from the center of vibration to approximately half of the stroke. Therefore, the spring constant of the biasing means is as shown in FIG. That is, at the deformation start position of the coil spring 9, the effective spring constant of the spring member changes discontinuously, and the spring constant of the biasing means also changes discontinuously.

According to this embodiment, similar to the embodiments described above, since the biasing means includes a spring member and a magnetic biasing means, a large acceleration can be obtained, and power can be supplied to the coil 4. It is possible to easily control the process.

Moreover, since the coil spring 9 is elastically deformed during a part of the stroke of the movable element 2, a large biasing force can be applied when the movable element 2 moves away from the center of vibration, and a large acceleration can be obtained. Although the spring constant of the biasing means changes discontinuously at the deformation start position of the coil spring 9, only the linear spring constant increases, and the control when supplying power to the coil 4 becomes complicated. Hateful.

Note that the present invention is not limited to the above-described embodiments, but includes other configurations that can achieve the object of the present invention, and the present invention also includes the following modifications.

For example, in the embodiment described above, the shafts 3A and 3B as guide means are inserted through the coil springs 8 and 9 as spring members, but the guide means do not need to be inserted through the spring members, for example. The coil spring may be compressed by disposing it between the moving magnet and the fixed magnet. If the guide means is not inserted through the guide means, the degree of freedom in the shape of the guide means can be improved, and the guide means can be formed in the form of a rail integrated with the case.

Furthermore, in the embodiment described above, the movable side magnets 24A, 24B and the stationary side magnets 6A, 6B each have two magnetic sections, but these magnets can be partitioned in any manner, and may be partitioned into three or more sections. or may have only one section. Further, the magnetic pole direction of the magnet constituting the magnetic biasing means does not have to be along the vibration direction, and for example, the magnetic pole direction may be substantially perpendicular to the vibration direction.

Furthermore, in the embodiment described above, the driving magnets are arranged in a Halbach arrangement, but they may be arranged in such a way that the N-pole and S-pole magnetic pole faces alternate. Furthermore, a configuration may be adopted in which a non-magnetic material is disposed between the north pole and the south pole, and any configuration may be used as long as a Lorentz force is generated in the X direction when current is passed through the coil.

In addition, the best configuration, method, etc. for carrying out the present invention have been disclosed in the above description, but the present invention is not limited thereto. That is, although the present invention has been specifically illustrated and described primarily with respect to particular embodiments, modifications may be made to the embodiments described above without departing from the spirit and scope of the invention. , materials, quantities, and other detailed configurations, those skilled in the art can make various modifications. Therefore, the descriptions that limit the shapes, materials, etc. disclosed above are provided as examples to facilitate understanding of the present invention, and do not limit the present invention. Descriptions of names of members that exclude some or all of the limitations such as these are included in the present invention.

1A, 1B Linear vibration actuator 2 Mover 22A to 22C Driving magnet (driving means)
24A to 24D Moving side magnet (magnetic biasing means)
3A, 3B Shaft (guiding means)
4 Coil (driving means)
5 Case (containment means)
6A to 6D Fixed side magnet (magnetic biasing means)
8, 9 Coil spring (spring member)

Claims (5)

a movable element capable of rectilinear vibration in a predetermined vibration direction;
accommodating means for accommodating the movable element;
a driving means that has a coil and a magnet and drives the movable element;
a biasing means for applying a biasing force to the movable element from both sides of the vibration direction;
The biasing means is configured separately from a spring member that applies the biasing force by elastic deformation and a magnet of the driving means, and is fixed to each of the movable element and the accommodation means. A linear vibration actuator comprising: magnetic biasing means that applies the biasing force by repulsive force between magnets. The linear vibration actuator according to claim 1, wherein the spring member is provided so as to be elastically deformed over the entire length of the stroke of the movable element. The linear vibration actuator according to claim 1, wherein the spring member is provided so as to be elastically deformed during a part of the stroke of the movable element. further comprising a guide means that extends in a rod shape along the vibration direction and guides the movable element;
4. The linear vibration actuator according to claim 1, wherein the spring member is a compression spring formed into a coil shape, and the guide means is inserted therethrough. The magnet of the driving means generates a driving force by having a magnetic pole direction substantially perpendicular to the vibration direction,
The linear vibration actuator according to claim 1, wherein the magnetic biasing means applies the biasing force by having a magnetic pole direction along the vibration direction.

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