JP2004266903A - Linear vibration actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem wherein the best use of the original performance of a magnet cannot be made, because the magnetization of a permanent magnet is difficult, and it cannot achieve size reduction and performance elevation as an actuator, in a linear vibration actuator where a permanent magnet is arranged within a hollow moving member and a stator is arranged via a magnetic gap. <P>SOLUTION: This linear vibration actuator uses a plurality of circular magnets 2A and 2B, with their magnetization being oriented in parallel, in the radial direction of the magnet center. Hereby, the magnetization of a small-diameter magnet can be facilitated. That is, the magnetization is carried out so that obverse and reverse become reverse poles by developing band-shaped flexible magnets, and the curled magnets are arranged within the moving member. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a linear vibration actuator.
[0002]
[Prior art]
Conventionally, an example of a linear vibration actuator will be described with reference to FIGS. FIG. 8 is a plan view of a linear vibration actuator in a conventional example (cover and spring are seen through), and FIG. 9 is a coaxial sectional view. A ring-shaped movable element 13 having a permanent magnet 12 disposed inside, and a coil portion 14 wound around the central portion of an axially symmetric core having an E-shaped cross section via a gap in the inner diameter thereof. The stator 15 is supported by an elastic body 16 so as to be movable in the axial direction (see, for example, Patent Document 1).
[0003]
The mover 13 vibrates up and down in accordance with the magnetic flux generated when an alternating current or pulse is applied to the coil portion 14. Supports 16 having one end fixed to the stator 15 and the other end fixed to the mover 13 are provided above and below the mover, and the kinetic energy of the mover is extracted as vibration.
[0004]
The permanent magnet having the inner diameter of the mover 13 has the same inner diameter and is magnetized to a single pole so as to be different from the outer diameter (for example, the inner diameter is N and the outer diameter is S).
[0005]
[Patent Document 1]
Application Publication No. 2001-358108 Publication Gazette
[Problems to be solved by the invention]
However, when the inner diameter of the magnet is as small as about 10 mm or less, there is a problem that magnetization is difficult. In particular, in order to improve the size and performance of the actuator, the magnet is required to have a high coercive force magnet having a high energy product and heat resistance. For example, SmCo sintered magnet. Magnetizing a high-performance SmCo sintered magnet requires a large magnetizing magnetic field of 4 MA / m or more. It is difficult to single-pole magnetize a small-diameter magnet having an inner diameter of about 10 mm or less as in this example, and there has been a problem in miniaturization and high performance as an actuator without utilizing the original performance of the magnet.
[0007]
[Means for Solving the Problems]
In the linear vibration actuator of the first invention according to the present application, a stator is arranged on an inner diameter of a hollow movable element via a magnetic gap, and a plurality of magnets are provided on the inner diameter of the hollow movable element, The side facing the stator is magnetized to the same pole, and is magnetized in parallel in the plate thickness direction of the magnet center.
[0008]
The linear vibration actuator according to a second aspect of the present application is the linear vibration actuator according to the first aspect, wherein the magnet is an arc-shaped magnet obtained by dividing the ring into two in the axial direction. They are spaced apart without touching.
[0009]
The linear vibration actuator of the third invention according to the present application is the linear vibration actuator of the second invention, wherein the linear vibration actuator of the second invention has a notch in at least one of the locations opposed to each other between the two magnets via the magnetic gap. Prepare a child.
[0010]
A linear vibration actuator according to a fourth aspect of the present application is the linear vibration actuator according to any one of the first to third aspects of the present invention, wherein at least a position between the magnets and a position facing each other via a magnetic gap is provided. A stator having a notch at one location is provided.
[0011]
According to a fifth aspect of the linear vibration actuator of the present application, a stator is provided on the inner diameter of the hollow movable element via a magnetic gap, and a strip-shaped flexible magnet is developed on the inner diameter of the hollow movable element. Then, magnetization is performed so that the front and back are opposite poles, curling and the side facing the stator are configured with the same pole.
[0012]
A linear vibration actuator according to a sixth aspect of the present application is the linear vibration actuator according to the fifth aspect of the present invention, wherein the stator has a cutout portion, and the mating surface of the flexible magnet curled with the cutout portion. It has a configuration of a positional relationship in which and are opposed.
[0013]
A linear vibration actuator according to a seventh aspect of the present application is the linear vibration actuator according to the fifth and sixth aspects of the present invention, in which a flexible magnet having a magnetization distribution inclined with respect to the thickness direction is curled. , Having a stator in which the side facing the stator of the magnet has the same pole and a notch is provided in at least one of the locations facing each other via a magnetic gap, and the notch and magnet are aligned by curling A magnetization distribution in which the magnetic flux is concentrated in a direction orthogonal to the depth direction in the stator radial direction of the notch is opposed to the surface portion.
[0014]
The linear vibration actuator according to an eighth aspect of the present application is the linear vibration actuator according to the seventh aspect of the present invention, wherein a flexible magnet is developed on a curved surface to perform parallel magnetization and tilted with respect to the thickness direction. A magnet having a magnetic distribution is provided.
[0015]
The linear vibration actuator according to a ninth aspect of the present application is the linear vibration actuator according to any of the first to eighth aspects, wherein the hollow movable element has a ring shape.
[0016]
According to a tenth aspect of the linear vibration actuator of the present application, in the linear vibration actuators of the first to eighth aspects, the hollow movable element has a circular inner shape and a polygonal outer side.
[0017]
An eleventh invention according to the present application is an information portable terminal on which the linear vibration actuator according to any of the first to tenth inventions is mounted. Also, it is installed in a mobile phone, PDA, game, watch, etc. instead of the information portable terminal.
[0018]
Thus, by using a plurality of arc-shaped magnets magnetized in parallel in the radial direction of the center of the magnet, single-pole magnetization of a small-diameter magnet can be easily performed, and a small high-performance linear vibration actuator can be provided. It is also possible to provide a small high-performance linear vibration actuator by deploying a band-shaped flexible magnet and magnetizing it so that the front and back have opposite poles and arranging the curled magnet on the inner diameter part of the mover Can do.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
The linear vibration actuator of the invention according to the present application has the following requirements.
A stator is arranged on the inner diameter of the hollow mover via a magnetic gap, and the inner diameter of the hollow mover is magnetized parallel to the radial direction of the center of the magnet, and the side facing the stator is magnetized to the same pole. In addition, the linear vibration actuator includes a plurality of magnets.
[0020]
In addition, the linear vibration actuator is characterized in that a belt-like flexible magnet is developed and magnetized so that the front and back have opposite poles, and the side facing the stator is curled.
[0021]
【Example】
Examples of the invention according to the present application will be described below.
[0022]
(Example 1)
1 and 2 show the configuration of the linear vibration actuator 1. FIG. 1 is a plan view of a linear vibration actuator in the present embodiment (a cover and a spring are shown as perspective views by dotted lines), and FIG. 2 is a coaxial sectional view.
[0023]
A ring-shaped movable element 3 having permanent magnets 2A and 2B arranged inside, and a coil part 4 wound around an axially symmetric core having an E-shaped cross section via a gap in the inner diameter thereof. And a stator 5 having an elastic body so that it can be moved in the axial direction.
[0024]
The mover 3 vibrates up and down in accordance with the magnetic flux generated when the coil portion 4 is energized. Spring 6 which is a support having one end fixed to the stator 5 and the other end fixed to the mover 3 is provided above and below the mover, and the kinetic energy of the mover is extracted as vibration.
[0025]
The permanent magnet having the inner diameter of the mover 3 is magnetized so that the side facing the stator has the same polarity and the back side of the permanent magnet facing the stator has a different polarity. For example, the side facing the stator is the N pole, and the back side of the side facing the stator is the S pole. Alternatively, the side facing the stator is the S pole, and the back side of the side facing the stator is the N pole.
[0026]
Here, the magnets 2A and 2B are magnets that are magnetized in parallel in the radial direction of the magnet center in the direction indicated by hatching, and are magnetized so that the inner diameter is the same pole in the orientation direction. In this embodiment, the magnet is divided and the parallel magnetization is performed to realize a magnetization state in which the inner diameter magnetization and the outer diameter magnetization are different from each other regardless of the small diameter. .
[0027]
Furthermore, by separating the mating surfaces 20 of the magnets 2A and 2B, the effect of demagnetizing fields that are opposite to each other is reduced, and the effective magnetic flux is increased. A notch 50 is provided in a portion of the stator 5 facing the mating surface 20 of the magnets 2A and 2B, and a portion having a small effective flux linkage is used as a wiring portion of the stator coil.
[0028]
Moreover, it shows to FIG. 3 (a), (b) about the example of a shape difference of a hollow shape needle | mover. The mover shown in FIG. 3A has a quadrilateral outer shape and a circular inner shape, and the mover 32 shown in FIG. 3B is a plan view of the mover having another shape according to the first embodiment. The rectangular shape and the inner shape are circular, and the weight of the mover can be increased more in a limited size, and the vibration can be obtained more compactly than in the conventional case.
[0029]
As described above, the hollow mover has a ring shape, a substantially cylindrical shape, or a substantially donut shape, and the outer shape and the inner shape of the hollow mover are appropriately selected according to the specifications of the linear vibration actuator. To do. These shapes are a circle, an ellipse, a polygon, and the like.
[0030]
As described above, in this embodiment, the stator is arranged on the inner diameter of the hollow movable element via the magnetic gap. A magnet is provided on the inner diameter of the hollow movable element. And the side facing this stator of the magnet is magnetized to the same pole, a plurality of magnets magnetized in parallel in the radial direction of the center of the magnet are arranged, the position between the magnets and the magnetic gap By adopting a configuration having a stator provided with a notch in at least one of the opposing locations, a small high-performance linear actuator can be provided. Furthermore, by mounting the linear vibration actuator of this embodiment on a mobile phone, PDA, game, watch, and information portable terminal, a small and high performance information portable terminal can be provided.
[0031]
(Example 2)
FIG. 4 shows another embodiment. FIG. 4 is a plan view of the mover and the stator of the second embodiment. A mover 30, a stator 5, and permanent magnets 21 and 23 are provided. 4A shows an example in which the magnet is divided into three parts, and FIG. 4B shows an example in which the magnet is divided into four parts.
[0032]
Here, the magnets 21 and 23 are magnets magnetized in parallel in the direction indicated by hatching, and are magnetized so that the side facing the stator has the same pole. In the present embodiment, the magnet is divided into three or four parts, and parallel magnetization is performed, thereby realizing a monopolar magnet having an inner diameter and an outer diameter that are different from each other despite a small diameter.
[0033]
4A, a notch 50 is provided in a portion of the stator 5 facing the mating surface 22 of the permanent magnet 21, and a portion having a small effective flux linkage is used as a wiring portion of the stator coil. .
[0034]
FIG. 4B shows another configuration of the second embodiment. A notch 50 is provided in a portion of the stator 5 facing the mating surface 24 of the permanent magnet 23, and a portion having a small effective flux linkage is used as a wiring portion of the stator coil.
[0035]
Thus, in this embodiment, a stator is arranged on the inner diameter of the hollow movable element via the magnetic gap, and the inner surface of the hollow movable element is magnetized on the same pole on the side facing the stator, As a configuration having a stator in which a plurality of magnets magnetized in parallel in the radial direction of the magnet center are arranged, and a notch is provided at at least one position between the magnets and a position facing each other via a magnetic gap Therefore, a small high-performance linear actuator can be provided.
[0036]
(Example 3)
FIG. 5 shows another embodiment. FIG. 5 is a plan view of the mover and stator of the third embodiment. Reference numeral 30 denotes a mover, 5 denotes a stator, and 25 denotes a permanent magnet. The permanent magnet of the present embodiment is a belt-like flexible magnet that is unfolded and magnetized so that the front and back have opposite poles, and is curled so that the side facing the stator has the same pole. Further, the position 26 on the mating surface of the curled permanent magnet is provided with a notch 50 at a location where the stator 5 is opposed via a magnetic gap. The wiring part. With such a configuration, a small high-performance linear actuator can be provided.
[0037]
Example 4
FIG. 6 shows another embodiment. FIG. 6A is a plan view of the mover and the stator of the fourth embodiment. Reference numeral 30 denotes a movable element, 5 denotes a stator, and 27 denotes a permanent magnet. FIG. 6B is a diagram showing a magnetized state of the magnet 27.
[0038]
The permanent magnet of this embodiment is a belt-like flexible magnet that is unfolded and magnetized so that the front and back are opposite poles. When the magnetization is performed, the parallel magnetization is performed in a state where the permanent magnet is not a flat surface but is developed on a curved surface having two peaks as shown in FIG. By curling this magnet, the magnetic flux can be concentrated on the B and D portions perpendicular to the stator notch shown in FIG. 6A, and the invalid magnetic flux in the vicinity of the notch 50 is reduced. be able to.
[0039]
FIG. 7 is a diagram showing the magnetization of a flexible permanent magnet. FIG. 7A shows a case in which the magnet is developed in a plane and parallel magnetized, and the effective magnet length of the permanent magnet 25 is M1 and equal to the plate thickness. On the other hand, FIG. 7 (b) shows a case where the two magnets are developed on a curved surface having two peaks as shown in the present embodiment and subjected to parallel magnetization. The plate thickness is M2, which is thicker than M1. With such a configuration, the demagnetization resistance can be increased, and the effective magnetic flux can be increased by increasing the permeance.
[0040]
As described above, the present embodiment has a configuration in which a flexible magnet is developed on a curved surface, performs parallel magnetization, and includes a magnet having a magnetization distribution inclined with respect to the plate thickness direction. An actuator can be provided.
[0041]
【The invention's effect】
As described above, according to the invention according to the present application, a stator is arranged on the inner diameter of the hollow movable element via a magnetic gap, and the parallel magnetization in the radial direction of the magnet center is arranged on the inner diameter of the hollow movable element. In addition, it is possible to easily realize a small high-performance linear vibration actuator by arranging a plurality of magnets magnetized to the same pole on the side facing the stator.
[0042]
In addition, a small, high-performance linear vibration actuator can also be obtained by developing a belt-shaped flexible magnet and magnetizing it so that the front and back have opposite poles and curling and facing the stator on the same pole. It can be easily realized.
[Brief description of the drawings]
FIG. 1 is a plan view of a linear vibration actuator of the present invention. FIG. 2 is an axial cross-sectional view of the linear vibration actuator of the present invention. FIG. 3A is a plan view of a mover of a first embodiment. [FIG. 4] (a) Plan view of the mover and stator of the second embodiment (b) Plan view of mover and stator of another configuration of the second embodiment [FIG. 5] Implementation FIG. 6A is a plan view of the mover and the stator of Example 4. FIG. 6B is a diagram showing the magnetized state of the magnet of Example 4. FIG. (A) The figure which shows the magnetization state of the magnet at the time of expand | deploying on the plane of Example 4 and carrying out parallel magnetization, (b) Expanding on the curved surface which gave the two peaks of Example 4, and carrying out parallel magnetization FIG. 8 is a plan view of the linear vibration actuator in the conventional example. FIG. 9 is a diagram of the linear vibration actuator in the conventional example. Rear view DESCRIPTION OF SYMBOLS
DESCRIPTION OF SYMBOLS 1 Bottom surface of linear vibration actuator 2A Permanent magnet 2B Permanent magnet 20 Mating surface of permanent magnet 2A and permanent 2B 3 Movable element 4 Coil part 5 Stator 50 Notch 6 Spring 7 Cover 11 Bottom view of linear vibration actuator 12 Permanent magnet 13 Movable Child 14 Coil portion 15 Stator 16 Spring 17 Cover

Claims (11)

A stator is arranged on the inner diameter of the hollow movable element via a magnetic gap, and a plurality of magnets are provided on the inner diameter of the hollow movable element, and the magnet is magnetized on the same pole on the side facing the stator, A linear vibration actuator that is magnetized in parallel in the plate thickness direction of the magnet center. The linear vibration actuator according to claim 1, wherein the magnet is an arc-shaped magnet obtained by dividing the ring into two in the axial direction, and the two magnets are spaced apart from each other without being in contact with each other. The linear vibration actuator according to claim 2, further comprising a stator having a notch at least at one of the locations facing each other between the two magnets with a magnetic gap interposed therebetween. The linear vibration actuator according to any one of claims 1 to 3, further comprising a stator having a notch at at least one of a position between the magnets and a position facing each other via a magnetic gap. A stator is provided on the inner diameter of the hollow movable element via a magnetic gap, and a belt-shaped flexible magnet is developed on the inner diameter of the hollow movable element so that the front and back surfaces are opposite to each other and magnetized. A linear vibration actuator in which the side facing the stator is configured with the same pole. The linear vibration actuator according to claim 5, wherein the stator has a notch portion, and has a configuration in which the notch portion and a curled flexible magnet mating surface face each other. Curling a flexible magnet having a magnetization distribution inclined with respect to the plate thickness direction, making the side facing the stator of the magnet the same pole, and notching at least one of the locations facing each other via a magnetic gap A stator provided with a portion, the notch portion and a mating surface portion by curling of the magnet are opposed to each other, and the magnetic flux is concentrated in a direction orthogonal to the depth direction of the stator radial direction of the notch portion. The linear vibration actuator according to claim 5, wherein the linear vibration actuator has a magnetization distribution. The linear vibration actuator according to claim 7, further comprising a magnet having a magnetized distribution in which a flexible magnet is developed on a curved surface to perform parallel magnetization and is inclined with respect to the thickness direction. The linear vibration actuator according to claim 1, wherein the hollow movable element has a ring shape. The linear vibration actuator according to claim 1, wherein the hollow movable element has a circular inner shape and a polygonal outer side. The information portable terminal carrying the linear vibration actuator in any one of Claims 1-10.

Images