JP2000004569A - Oscillating actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oscillating actuator, whose assembling variance has no influence on properties and which can reduce the number of parts for an inexpensive structure, and is superior in elementary properties and durability. SOLUTION: In this oscillating actuator, the shape of a drop-off stopper 4a coming into contact with a damper 8 on a center shaft 4 is improved and the stopper 4a is brought into contact with the damper 8 though a step 11, which is formed so that its cross section may be arc-shaped. This oscillating actuator is structured so as to movably support (a plate 3 is disposed between the damper 8 and a permanent magnet 2, and a cushioning 9 is disposed between a fulcrum 10 and a yoke 1) a magnetic circuit (disposed concentric with a coil 5 disposed at a gap between the sidewall of the yoke 1 and the end surface of the permanent magnet 2 and fixed to a coil positioning part 7) consisting of the yoke 1, the permanent magnet 2, and the plate 3, and integrate a spring function at one point of damper 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration actuator mainly mounted on a mobile communication device such as a portable telephone and having a function of generating vibration.

[0002]

2. Description of the Related Art Conventionally, as a vibration actuator of this type, there is one having a structure as shown in FIG. 11, for example. In this vibration actuator, a magnetic circuit is movably supported by a center shaft 34 using a damper 38 and a support rubber 42 with respect to a support base 40.

More specifically, the damper 38 has a coil support portion 36 at the periphery on one main surface side, and has a coil positioning portion 37 formed by cutting out the outer peripheral portion of the coil support portion 36. ing. A central shaft 34 having a retaining portion 34a extending perpendicular to the axial direction and having contact with the damper 38 is fitted to a central portion on one main surface side of the damper 38. The magnetic circuit has a yoke 31 mounted on the central shaft 34 with an air gap between the damper 38 and a yoke 31 mounted on the central shaft 34 with an air gap between the damper 38 and the side wall of the yoke 31 inside the yoke 31. Disk-shaped permanent magnet 32 provided separately from
And a plate 33 interposed between the damper 38 and the permanent magnet 32.

[0004] The magnetic circuit here is arranged concentrically with respect to a coil 35 which is provided in a gap between the side wall of the yoke 31 and the end face of the permanent magnet 32 and is fixed to the coil positioning portion 37 of the damper 38.

In this vibration actuator, the damper 38
And a claw-like projection 4 formed on the peripheral edge of the support base 40 with a plate 33 interposed between the permanent magnet 32 and a buffer material 39 between the support base 40 and the yoke 31.
The magnetic circuit is movably supported by locking the support rubber 42 with respect to 1.

Incidentally, a vibration actuator having such a configuration has been proposed by the present applicant as a vibration actuator for a pager disclosed in Japanese Patent Application No. 8-324997.

In the case of this vibration actuator, the coil 3
When a current is supplied to the coil 5 in one direction, a downward force is generated according to Fleming's left-hand rule, and the magnetic circuit is displaced in a direction away from the coil 35. The damper 38 and the supporting rubber 42 flexibly support the displacement at this time, and have a spring function of restoring the magnetic circuit to the original position.

FIG. 12 shows the relationship between the load acting on the spring function of the vibration actuator and the amount of displacement associated therewith. However, in the drawing, the characteristic of the damper 38 is C1, the characteristic of the support rubber 42 is C2, and the combined characteristic of the damper 38 and the support rubber 42 is C3.

Here, it is shown that the combined characteristic C3 is obtained by combining the characteristic C1 of the damper 38 with a small spring constant and the characteristic C2 of the support rubber 42 with a large spring constant. The above shows that since the support rubber 42 is loosely assembled, the magnetic circuit exerts a spring property from the intersection _CX after being displaced to some extent.

Generally, in a vibration actuator,
If the input is constant during the vibration, a certain amplitude is necessary to obtain a satisfactory vibration, but if the amplitude is too large, the vibration becomes too large, not only generating unnecessary noise, but also There is a problem that the life of the spring function is shortened.

Therefore, by combining two types of springs, the damper 38 and the support rubber 42, as in the above-described vibration actuator, and forming a non-linear spring function, an appropriate amplitude (displacement amount) can be stably obtained. Like that.

[0012]

In the case of the above-described vibration actuator, the intersection _CX in the characteristic of the support rubber 42 having a spring function is apt to vary at the time of assembling, and the intersection _CX shifts to the displacement decreasing side (the left side in FIG. 12). Then, the vibration output is weakened and an appropriate amplitude cannot be obtained. Conversely, if the intersection _CX shifts to the displacement increasing side (the right side in FIG. 12), the amplitude becomes too large and adversely affects noise generation and spring life. In addition, there is a problem that variations in assembly greatly affect characteristics, and the damper 38 and the support rubber 42
In order to combine the two types of springs, there is a problem that assembling man-hours are required, the number of parts is increased, and parts costs and management costs are increased.

Further, when the amplitude becomes too large due to the variation of the intersection _CX at the time of assembling, noise is generated or the life of the spring is deteriorated due to the displacement operation of the magnetic circuit accompanied by shaft runout. And the shape of the retaining portion 34a of the central shaft 34 which is in contact with the damper 38 (the cross-sectional shape having a large contact area with the damper 38 is a rectangular flange). Structural improvements are also desired.

The present invention has been made to solve such a problem, and its technical problem is that the variation in assembly does not greatly affect the characteristics, and the cost is reduced while reducing the number of parts. An object of the present invention is to provide a vibration actuator having excellent basic characteristics and durability characteristics.

[0015]

According to the present invention, a flexible damper having a coil positioning portion formed on a peripheral edge on one main surface side, and a center shaft fitted to a central portion of the damper on one main surface side And a magnetic circuit including a permanent magnet mounted on the central shaft with a gap between the damper and a coil disposed in the gap and mounted and fixed to the coil positioning section. A vibration actuator having a stopper which is concentrically arranged with respect to the coil and is movably supported, and wherein the central axis extends perpendicularly to the axial direction and has a retaining portion which comes into contact with the damper; The stop portion forms a step and abuts against the damper, and the vibration actuator is formed such that the cross section of the step forms an arc shape.

Further, according to the present invention, a flexible damper having a coil positioning portion formed on a peripheral edge on one main surface side, a center shaft fitted to a central portion of the damper on one main surface side, and a damper; A magnetic circuit including a permanent magnet mounted on the central axis with a gap therebetween, and a coil disposed in the gap and mounted and fixed to the coil positioning portion, and the magnetic circuit is mounted on the coil with respect to the coil. In a vibration actuator having a retaining portion that is concentrically arranged and movably supported, and the central axis extends perpendicularly to the axial direction and that comes into contact with the damper, the retaining portion includes: As a result, a vibration actuator can be obtained in which a step is formed and abuts against the damper, and the sectional shape of the step is formed so as to form a gradient with respect to the damper.

Further, according to the present invention, a flexible damper having a coil positioning portion formed on a peripheral edge on one main surface side, a center shaft fitted to a central portion of the damper on one main surface side, A magnetic circuit including a permanent magnet mounted on the central axis with a gap therebetween, and a coil disposed in the gap and mounted and fixed to the coil positioning portion, and the magnetic circuit is mounted on the coil with respect to the coil. In a vibration actuator having concentrically arranged and movably supported, and the center axis extending perpendicularly to the axial direction and having a retaining portion abutting on the damper, the vibration actuator has An annular member arranged and attached to the central shaft is provided, and the retaining portion and the annular member are
It is possible to obtain a vibration actuator in which a step is formed and abuts against the damper, and the cross section of the step is formed to have an arc shape.

In addition, according to the present invention, a flexible damper having a coil positioning portion formed on a peripheral edge on one main surface side, a center shaft fitted to a central portion of the damper on one main surface side, and a damper A magnetic circuit including a permanent magnet mounted on the central axis with a gap between the coil, and a coil disposed in the gap and mounted and fixed to the coil positioning portion, and the magnetic circuit with respect to the coil In a vibration actuator having a retaining portion which is concentrically arranged and movably supported, and whose central axis extends perpendicularly to the axial direction and abuts on the damper, a clearance inside the coil is provided. The annular member is disposed on the central axis and is attached to the center shaft.The stopper portion and the annular member form a step and abut against the damper, and the sectional shape of the step forms a gradient with respect to the damper. Formed vibration actuator Obtained.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The vibration actuator of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a perspective view of the vibration actuator according to the first embodiment of the present invention, in which the external configuration is partially cut away. FIG. 2 is a plan view showing the external configuration of the vibration actuator with a part cut away. FIG. 3 is a side sectional view showing a basic configuration of the vibration actuator.

In the case of this vibration actuator, the shape of the retaining portion 4a in contact with the damper 8 of the center shaft 4 is improved as compared with the ready-made product shown in FIG.
1 and abut on the damper 8, and the step 11 is formed so that the cross-sectional shape of the step 11 is formed in an arc shape. And a magnetic circuit comprising the plate 3 (disposed concentrically with the coil 5 provided in the gap between the side wall of the yoke 1 and the end face of the permanent magnet 2 and fixed to the coil positioning portion 7 of the damper 8). The difference lies in the structure in which the support and the spring function are integrated at one point of the damper 8.

That is, also in this case, the periphery of the damper 8 on one main surface side is the coil supporting portion 6 and has the coil positioning portion 7 formed by cutting out the outer peripheral portion of the coil supporting portion 6. . A central shaft 4 having a retaining portion 4a extending perpendicular to the axial direction and having a contact with the damper 8 is fitted to a central portion on one main surface side of the damper 8. The magnetic circuit is the same as the conventional one, and the yoke 1 is attached to the central shaft 4 with a gap between the damper 8 and the yoke 1 is attached to the central shaft 4 with a gap between the damper 8. It comprises a disk-shaped permanent magnet 2 which is installed in the interior thereof so as to be separated from its side wall, and a plate 3 interposed between the damper 8 and the permanent magnet 2. Also, the magnetic circuit here is arranged concentrically with the coil 5 which is provided in the gap between the side wall of the yoke 1 and the end face of the permanent magnet 2 and is fixed to the coil positioning portion 7 of the damper 8.

In this vibration actuator, the plate 3 is interposed between the damper 8 and the permanent magnet 2, the cushioning material 9 is interposed between the support 10 and the yoke 1, and the center shaft 4 having the retaining portion 4a is used. The magnetic circuit and the damper 8 are coaxially positioned and fixed so that the magnetic circuit is movably supported, so that the spring function is integrated at one point of the damper 8.

Among them, a damper 8 having a center hole for mounting the center shaft 4 and having a coil positioning portion 7 formed concentrically with the center hole in the coil support portion 6 is as follows.
It is formed integrally with a resin material or a metal material, or further processed. The coil 5 includes a coil positioning unit 7
Is assembled into the space of the magnetic circuit with the magnetic circuit being concentrically positioned in a space having a high magnetic flux density. The coil support 6 is fixed to the support 10 by bonding or the like. At this time, it is also effective to interpose an elastic material (not shown) between the support 10 and the coil support 6. The cushioning material 9 is fixed to the support base 10 by bonding or the like between the yoke 1 and the support base 10 of the magnetic circuit so that the magnetic circuit collides with the support base 10 to suppress generation of unnecessary sound. Note that the support base 10 is fixed to the housing 12 by bonding or the like. The damper 8 is provided with a spiral slit as shown in FIG. 2 so that the damper 8 can be flexibly supported in the axial direction of the central shaft 4. That is, the damper 8
When the magnetic circuit vibrates up and down in FIG. 3, it flexibly supports this and functions as a leaf spring restored to the initial state. Strictly speaking, the cross section of the damper 8 is not continuous in a side cross section as shown in FIG. 3, but is simplified and continuously drawn here.

In this vibration actuator, when a drive signal of a single frequency of about 100 Hz is input to the coil 5, the coil 5 is located in the gap of the magnetic circuit.
According to Fleming's left-hand rule, the coil 5 and the magnetic circuit vibrate in synchronization with a relatively input frequency, and the vibration is output to the outside via the housing 12.

FIG. 4 is a side sectional view shown for explaining one operation state of the vibration actuator. FIG. 5 is a sectional side view for explaining another operation state of the vibration actuator.

In this vibration actuator, when a drive signal is input, the magnetic circuit is pushed downward by a force generated according to Fleming's left-hand rule, and at this time, the damper 8 is elastically deformed with the displacement of the magnetic circuit. Damper 8
In the example, the central portion is a step 1 in the retaining portion 4a of the central shaft 4.
1 and no further deformation occurs. Since the step 11 has an arc-shaped cross section, the contact point with the damper 8 changes continuously with the displacement of the magnetic circuit.

That is, when the damper 8 is assumed to be a leaf spring, the length of the leaf spring changes continuously in proportion to the displacement of the magnetic circuit. From the state where there is no displacement amount of the magnetic circuit to the state where the displacement amount shown in FIG. 5 becomes the maximum through the slightly displaced state shown in FIG. 4 (the leaf spring length of the damper 8 becomes the shortest at this time). The state transition process is repeated.

FIG. 6 shows the relationship between the load acting on the spring function of the vibration actuator and the amount of displacement associated therewith. When the spring function of this vibration actuator is considered as a leaf spring, the length of the leaf spring does not change until a certain amount of displacement, so that the leaf spring has the same linear shape as a normal leaf spring. Therefore, it becomes non-linear as shown. The nonlinear curve in FIG. 6 can be freely set by changing the cross-sectional shape of the step 11 in the retaining portion 4a of the center shaft 4.

Next, in this vibration actuator,
When a driving signal of a single frequency of about 2 kHz is input to the coil 5, the coil 5 and the magnetic circuit vibrate relatively in synchronization with the input frequency, and the vibration of the coil 5 is transmitted to the housing 12,
This causes the housing 12 to vibrate, but the frequency is 2 kHz.
Because it is high before and after, it enters the human audible range and sounds as a buzzer. When a drive signal in the audio band of several hundreds to several thousands Hz is input to the coil 5, the housing 12 becomes a diaphragm and outputs audio in the same manner as a normal speaker.

FIG. 7 is a side sectional view showing a basic configuration of a vibration actuator according to Embodiment 2 of the present invention. In the case of this vibration actuator, the retaining portion 4b forms a step 13 and abuts on the damper 8 as compared with that of the first embodiment, and the sectional shape of the step 13 is formed so as to form a gradient with respect to the damper 8. Are different.

FIG. 8 shows the relationship between the load acting on the spring function of the vibration actuator and the amount of displacement associated therewith. In the case of this vibration actuator, since the step 13 in the retaining portion 4b of the center shaft 4 is inclined with respect to the damper 8, the length of the leaf spring of the damper 8 changes with displacement of the magnetic circuit by 1 And a non-linear curve as shown. It should be noted that the non-linear curve in FIG.
Can be freely set by changing the cross-sectional shape of.

FIG. 9 is a side sectional view showing a basic configuration of a vibration actuator according to Embodiment 3 of the present invention. In the case of this vibration actuator, an annular member 15 is provided between the damper 8 and the plate 3 and is attached to the center shaft 4 in the gap inside the coil 5 as compared with that of the first embodiment. The difference is that the annular member 15 and the retaining portion 4a of the center shaft 4 form a step 14 and abut on the damper 8, and the cross-sectional shape of both these steps 14 is formed in an arc shape. I have. In the configuration of the first and second embodiments, the leaf spring of the damper 8 is nonlinear only in one direction. However, in the configuration of the third embodiment, the leaf spring is nonlinear in both upper and lower directions. Example 1,
The cushioning material 9 used in the configuration 2 becomes unnecessary.

FIG. 10 is a side sectional view showing a basic configuration of a vibration actuator according to Embodiment 4 of the present invention. In the case of this vibration actuator, compared to the second embodiment,
The gap inside the coil 5, the damper 8 and the plate 3
An annular member 17 is provided therebetween and attached to the center shaft 4. The annular member 17 forms a step 16 with the retaining portion 4 b of the center shaft 4 to contact the damper 8, and The difference is that the cross-sectional shapes of both steps 16 are formed so as to form a gradient with respect to the damper 8. Also, in the case of the configuration of the fourth embodiment, the cushioning material 9 used in the configurations of the first and second embodiments becomes unnecessary because the configuration is nonlinear in both the up and down directions.

Also in the case of the vibration actuators of the third and fourth embodiments, the cross-sectional shape of the retaining portion 4a of the central shaft 4 and the step 14 of the annular member 15 and the retaining portion 4b of the central shaft 4 And annular member 17
The nonlinear curve can be set freely by changing the cross-sectional shape of the step 16 at.

[0036]

As described above, according to the vibration actuator of the present invention, the shape of the retaining portion which comes into contact with the central shaft damper in the existing product is improved, and the vibration actuator comes into contact with the damper by forming a step. In addition, the cross-sectional shape of the step is formed so as to form an arc shape, or is formed so as to form a gradient with respect to the damper, and furthermore, the central axis is disposed in a gap between the damper and the magnetic circuit. The shape of the retaining portion and the annular member is improved by providing an annular member to be attached to the damper. Similarly, a step is formed to contact the damper, and the cross section of the step is formed to form an arc shape. Or a structure that forms a gradient with respect to the damper. With this configuration, the leaf spring function of the damper is made non-linear, and the spring function conventionally performed by the two-point parts of the damper and the supporting rubber is damped. Since you are aggregate structure at one point, variations in assembly without increasing effect on the properties, yet it reduces the number of components becomes excellent basic characteristics and durability characteristics. As a result, it becomes possible to provide a vibration actuator in which the variation in assembly does not greatly affect the characteristics, and it is possible to improve the component cost, the assembly cost, the management cost, etc. by reducing the number of components, thereby reducing the cost of the vibration actuator. An actuator can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view of a vibration actuator according to a first embodiment of the present invention, in which the external configuration is partially cut away.

FIG. 2 is a plan view of the vibration actuator shown in FIG.

FIG. 3 is a side sectional view showing a basic configuration of the vibration actuator shown in FIG.

FIG. 4 is a side sectional view shown for explaining one operation state of the vibration actuator shown in FIG. 1;

FIG. 5 is a side sectional view shown for explaining another operation state of the vibration actuator shown in FIG. 1;

6 shows a relationship between a load acting on a spring function of the vibration actuator shown in FIG. 1 and a displacement amount accompanying the load.

FIG. 7 is a side sectional view showing a basic configuration of a vibration actuator according to a second embodiment of the present invention.

FIG. 8 shows a relationship between a load acting on a spring function of the vibration actuator shown in FIG. 7 and an amount of displacement accompanying the load.

FIG. 9 is a side sectional view showing a basic configuration of a vibration actuator according to a third embodiment of the present invention.

FIG. 10 is a side sectional view showing a basic configuration of a vibration actuator according to a fourth embodiment of the present invention.

FIG. 11 is a side sectional view showing a basic configuration of a conventional vibration actuator.

FIG. 12 shows a relationship between a load acting on a spring function of the vibration actuator shown in FIG. 11 and a displacement amount accompanying the load.

[Explanation of symbols]

 1,31 Yoke 2,32 Permanent magnet 3,33 Plate 4,34 Center axis 4a, 4b, 34a Detachment prevention part 5,35 Coil 6,36 Coil support part 7,37 Coil positioning part 8,38 Damper 9,39 Buffer Material 10, 40 Support base 11, 13, 14, 16 Step 12 Housing 15, 17 Ring member 41 Shaped projection 42 Support rubber

Claims (4)

[Claims] 1. A flexible damper having a coil positioning portion formed on a peripheral edge on one main surface side, a center shaft fitted to a central portion of the damper on the one main surface side, and the damper A magnetic circuit including a permanent magnet mounted on the center axis with a gap, and a coil disposed in the gap and fixedly mounted on the coil positioning portion, and the magnetic circuit is mounted on the coil with respect to the coil. In a vibration actuator having a retaining portion which is concentrically arranged and movably supported, and whose central axis extends perpendicularly to the axial direction and which comes into contact with the damper, the retaining portion is preferably A vibration actuator, wherein a step is formed to abut on the damper, and the cross section of the step is formed in an arc shape. 2. A flexible damper having a coil positioning portion formed on a peripheral edge on one main surface side, a center axis fitted to a central portion of the damper on the one main surface side, and the damper. A magnetic circuit including a permanent magnet mounted on the center axis with a gap, and a coil disposed in the gap and fixedly mounted on the coil positioning portion, and the magnetic circuit is mounted on the coil with respect to the coil. In a vibration actuator having a retaining portion which is concentrically arranged and movably supported, and whose central axis extends perpendicularly to the axial direction and which comes into contact with the damper, the retaining portion is preferably A vibrating actuator, wherein the vibrating actuator is formed so as to form a step and abut on the damper, and the cross-sectional shape of the step forms a gradient with respect to the damper. 3. A flexible damper having a coil positioning portion formed on a peripheral edge on one main surface side, a center shaft fitted to a central portion of the damper on the one main surface side, and the damper. A magnetic circuit including a permanent magnet mounted on the center axis with a gap, and a coil disposed in the gap and fixedly mounted on the coil positioning portion, and the magnetic circuit is mounted on the coil with respect to the coil. In a vibration actuator, which is concentrically arranged and movably supported, and whose central axis extends perpendicularly to the axial direction and has a retaining portion that comes into contact with the damper, An annular member disposed in the gap and attached to the central shaft, wherein the stopper portion and the annular member form a step and abut against the damper, and the cross section of the step forms an arc shape. It is specially formed Vibration actuator. 4. A flexible damper having a coil positioning portion formed on a peripheral edge on one main surface side, a center axis fitted to a central portion on the one main surface side of the damper, and the damper. A magnetic circuit including a permanent magnet mounted on the center axis with a gap, and a coil disposed in the gap and fixedly mounted on the coil positioning portion, and the magnetic circuit is mounted on the coil with respect to the coil. In a vibration actuator, which is concentrically arranged and movably supported, and whose central axis extends perpendicularly to the axial direction and has a retaining portion that comes into contact with the damper, An annular member disposed in the gap and attached to the central shaft, wherein the retaining portion and the annular member form a step and abut against the damper, and a cross-sectional shape of the step is relative to the damper. Formed to form a gradient A vibration actuator characterized by being performed.