JP2001062396A - Vibration actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent decrease in sound pressure level even in the case of being fixed on a vibration transmitting device. SOLUTION: Double face tapes 12 as an elastic substance for setting a supporting stand 1 on a casing 19 of an external portable telephone terminal through a vibration plate 18 are fixed on the side of one main face of the supporting stand 7 and also on another main face on the opposite side on a vibration actuator, and a positioning protrusion 18a for positioning the supporting stand 7 is formed on the vibration plate 18, while a positioning protrusion 19a for positioning the vibration plate 18 is formed on the casing 19 of the portable telephone terminal, and for the purpose of transmitting the vibration on the supporting stand 7 of the vibration actuator, sections between the supporting stand 7 and the vibration plate 18 and also between the vibration plate 18 and the casing 19 of the portable telephone terminal are clamped respectively by double face tapes 12 and 13 and fixed to transmit the vibration of the supporting stand 7 to the casing 19 of the portable telephone terminal through the vibration plate 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration actuator which is mounted on a mobile communication device (vibration transmitting device) such as a portable telephone terminal and drives a coil and a magnetic circuit by an input electric signal. .

[0002]

2. Description of the Related Art Conventionally, as a vibration actuator of this type, for example, there is a vibration actuator having a structure as shown in a side sectional view of FIG.

[0003] This vibration actuator has a central shaft 4 mounted on a support base 7 through an elastic damper 6.
Thereby movably supports a magnetic circuit composed of the permanent magnet 2, the yoke 1, and the plate 3.

[0004] More specifically, the damper 6 is configured such that the outer periphery 6a on one main surface side is cut out so that the coil 5 can be positioned and mounted. A central shaft 4 having a retaining portion that extends perpendicularly to the one axial direction and comes into contact with the damper 6 is fitted into the penetrating central hole. The magnetic circuit includes a yoke 1 mounted on the central shaft 4 with a gap between the damper 6 and a magnetic circuit mounted on the central shaft 4 with a gap between the damper 6 and a side wall of the yoke 1 inside the yoke 1. The permanent magnet 2 includes a disk-shaped permanent magnet 2 and a plate 3 interposed between the damper 6 and the permanent magnet 2. That is, in the case of the vibration actuator here, the magnetic circuit and the damper 6 are positioned coaxially by the center axis 4, and the magnetic circuit is formed by the side wall of the yoke 1 and the permanent magnet 2.
It is arranged in the gap between the end faces, is arranged concentrically with the coil 5 mounted on the outer peripheral portion 6a of the damper 6, and is supported so as to be able to move flexibly in one axial direction (vertical direction).

In the case of this vibration actuator, the coil 5
When an oscillating current is supplied in one direction, an upward force is generated according to the rule of Filling's left hand, and the magnetic circuit is displaced in a direction away from the coil 5, so that the magnetic circuit is supported from the outer peripheral portion 6a of the damper 6 by the coil 5. Vibration can be transmitted to the outside via the base 7. Therefore, the support base 7 of such a vibration actuator can be mounted on an external vibration transmission device with a diaphragm interposed.

FIG. 6 shows a main part configuration in the case where the vibration actuator is used to fix to a housing 9 of a portable telephone terminal as a vibration transmission device via a diaphragm 8. ) Relates to a plan view, and FIG. 13B relates to a partially cut-away side view.

In this case, a support 7 for the vibration actuator is provided.
In order to transmit the vibration at the outside to the outside, the space between the support 7 and the vibration plate 8 and the space between the vibration plate 8 and the housing 9 of the mobile phone terminal are fixed by adhesives 10 and 11, respectively.
This shows that the vibration of the support base 7 is transmitted to the housing 9 of the mobile phone terminal via the diaphragm 8.

[0008]

When the above-described vibration actuator is used to fix to a vibration transmitting body via a vibration plate, the housing between the support base and the vibration plate and the vibration plate and the vibration transmission device (portable telephone terminal). When the vibration of the magnetic circuit is transmitted from the support base to the diaphragm and further from the diaphragm to the housing of the vibration transmission device (mobile phone terminal) because the body and the body are fixed with an adhesive, There is a problem that the sound pressure level generated from the actuator is reduced due to the transmission of the adhesive through a hard material called attenuation to cause attenuation.

The present invention has been made in order to solve such problems, and a technical problem thereof is to provide a vibration actuator having a structure in which the sound pressure level does not decrease even when the vibration actuator is fixed to a vibration transmission device. It is in.

[0010]

According to the present invention, a magnetic circuit is movably supported by a central shaft mounted on a support base via an elastic damper, and a peripheral edge of an outer peripheral portion of the damper is provided. The coil and the magnetic circuit are driven by the input of an electric signal to the coil arranged in the gap of the magnetic circuit positioned and mounted on the magnetic circuit, and can be mounted to an external vibration transmission device via the diaphragm. In the vibration actuator, at least one of the space between the support and the vibration plate and the space between the vibration plate and the housing of the device to be vibrated is sandwiched by an elastic substance and mounted and fixed.

In this vibration actuator, a projection or a groove for positioning the support base is formed on the diaphragm, and a projection or a groove for positioning the diaphragm is formed on the housing of the vibration transmission device. Is preferred.

On the other hand, according to the present invention, the magnetic circuit is movably supported by the center shaft mounted on the support base via the elastic damper, and is positioned and mounted on the outer peripheral portion of the damper. In the vibration actuator, the coil and the magnetic circuit are driven by the input of an electric signal to the coil disposed in the gap of the magnetic circuit, and further, the support table and the vibration actuator can be directly mounted on an external vibration transmission device. A vibration actuator can be obtained in which the housing of the vibration transmission device is sandwiched and fixed with an elastic substance and mounted.

In this vibration actuator, it is preferable that a convex portion or a groove portion for positioning the support table is formed in the housing of the transmission device.

On the other hand, in any one of the above-mentioned vibration actuators, a vibration actuator can be obtained in which the elastic material is subjected to heat mounting, press-fitting, or screw fixing for mounting and fixing between members.

In this vibration actuator, the elastic substance is preferably a double-sided tape or a foam-based material.

[0016]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a side sectional view showing a basic structure of a vibration actuator according to one embodiment of the present invention. The configuration of this vibration actuator is also substantially the same as that of the conventional product described with reference to FIG. 5, and the permanent magnet 2, the yoke 1, and the center shaft 4 are mounted on the support base 7 via the elastic damper 6. The magnetic circuit constituted by the plate 3 is movably supported.

That is, the damper 6 has an outer peripheral portion 6a on one main surface side which is notched so that the coil 5 can be positioned and mounted. A center hole penetrating the central portion on one main surface side is provided. Is fitted with a central shaft 4 having a retaining portion which extends perpendicularly to one axial direction and comes into contact with the damper 6. The magnetic circuit includes a yoke 1 mounted on the central shaft 4 with a gap between the damper 6 and a magnetic circuit mounted on the central shaft 4 with a gap between the damper 6 and a side wall of the yoke 1 inside the yoke 1. The permanent magnet 2 includes a disk-shaped permanent magnet 2 and a plate 3 interposed between the damper 6 and the permanent magnet 2. Also in the case of the vibration actuator here, the magnetic circuit and the damper 6 are positioned coaxially by the center shaft 4, and
The magnetic circuit is disposed in a gap between the side wall of the yoke 1 and the end face of the permanent magnet 2 and is arranged concentrically with the coil 5 mounted on the outer peripheral portion 6a of the damper 6, and is flexible in one axial direction (vertical direction). It is supported to be movable.

Incidentally, in each part here, the support 7
The central shaft 4 and the damper 6 may be fixed by press-fitting, bonding, caulking, or the like, but the central shaft 4 and the damper 6 may be made of the same material. Welding becomes possible.

Further, in the case of this vibration actuator, an elastic material for mounting the support 7 to an external vibration transmission device with a diaphragm interposed on the main surface opposite to the one main surface of the support 7. , A double-sided tape 12 is fixed.

FIG. 2 shows a main part configuration in the case where the vibration actuator is used to fix to a housing 19 of a portable telephone terminal as a vibration transmitting body via a diaphragm 18.
FIG. 1A relates to a plan view, and FIG. 2B relates to a partially cut-away side sectional view.

In this case, as described above, the support 7 is mounted on the external housing 19 of the portable telephone terminal with the diaphragm 18 interposed on the main surface opposite to the one main surface of the support 7 as described above. The double-sided tape 12 is fixed, while the diaphragm 18 has a positioning protrusion 1 for positioning the outer diameter of the support 7.
8a is formed, and the diaphragm 1 is provided on the housing 19 of the mobile phone terminal.
A positioning protrusion 19a for positioning the outer diameter of the vibration plate 8 is formed, and the support 7 and the vibration plate 1 are used to transmit the vibration of the support 7 of the vibration actuator to the outside.
8 and the space between the vibration plate 18 and the housing 19 of the mobile phone terminal are sandwiched and fixed with double-sided tapes 12 and 13 as elastic substances, respectively, so that the vibration of the support base 7 is reduced.
8 to the case 19 of the mobile phone terminal.

In this vibration actuator, when the vibration of the magnetic circuit is transmitted from the support base 7 to the diaphragm 18 and further from the diaphragm 18 to the housing 19 of the portable telephone terminal, the double-sided tapes 12 and 13 are used. The sound pressure level generated from the actuator is kept good and large without being attenuated due to transmission in a soft substance.

In order to increase the mechanical strength, it is preferable that the double-sided tapes 12 and 13 are further mounted on the double-sided tapes 12 and 13 by heat staking, press-fitting, or screwing.

FIG. 3 is a side view showing the structure of the double-sided tapes 12 and 13 used in the vibration actuator.

The double-sided tapes 12 and 13 are formed by applying an adhesive 16 on both sides of a base material 15. Since the adhesive 16 has elasticity, vibration transmission is improved. Base material 15 here
Include nonwoven fabric, polyester film, foamed butyl rubber,
It is preferable to use any one of foamed polyethylene.

FIG. 4 compares the characteristics of the sound pressure level (dB) with respect to the frequency (Hz) of the vibration actuator having the structure of the embodiment described in FIG. 2 and the vibration actuator having the conventional structure described in FIG. It is shown.

From FIG. 4, the conventional structure shown by a solid line in which three points between the support 7 and the diaphragm 8 and between the diaphragm 8 and the housing 9 of the portable telephone terminal are fixed with adhesives 10 and 11 is shown. The structure of the embodiment shown by dotted lines in which three points between the vibration actuator and the support 7 and the diaphragm 18 and between the diaphragm 18 and the housing 19 of the mobile phone terminal are fixed with double-sided tapes 12 and 13. As a result of sound pressure measurement, it can be seen that the sound pressure level of the structure of the embodiment is improved by about 15 dB as compared with that of the conventional structure.

In the vibration actuator of the above-described embodiment, the positioning projections 18a formed on the vibration plate 18 are provided.
In addition, the positioning projection 19a formed on the housing 19 of the mobile phone terminal determines the outer diameter of the support base 7 and the diaphragm 18, but the inner diameter is determined instead of the outer diameter, or It is also possible to install so as to position both the inner and outer diameters, and it is also possible to use a positioning groove instead of the positioning projection. In the case of the vibration actuator of one embodiment, the space between the support 7 and the vibration plate 18 and the space between the vibration plate 18 and the housing 19 of the mobile phone terminal are fixed by being sandwiched between the double-sided tapes 12 and 13 as elastic materials. Although the configuration is adopted, a foam-based material may be used instead of the double-sided tapes 12 and 13. However, also in the case of this configuration, it is desirable to further increase the mechanical strength of the foam-based material by performing heat fixing, press-fitting, and screw fixing between the members from above. Further, in the case of the vibration actuator according to the embodiment, the vibration actuator 18 can be attached to an external vibration transmission device via the vibration plate 18, but can be directly attached to the external vibration transmission device instead. It can also be set as a structure. In this case, specifically, the support 7
A positioning for positioning the support 7 only on the mobile phone terminal housing 19 by sandwiching between the double-sided tape 12 and the foam material as an elastic material between the housings 19 of the mobile phone terminal. What is necessary is just to be the structure which forms the convex part 19a and the positioning groove part. In any case, the characteristic that the sound pressure level is improved is obtained as shown by the dotted line in FIG.

[0030]

As described above, according to the vibration actuator of the present invention, the vibration is not attenuated when the vibration is transmitted by being mounted on the external vibration transmission device from the support base.
When it is possible to attach the external vibration transmission device via the diaphragm, the external vibration transmission device is sandwiched between the support table and the vibration plate and the vibration plate and the housing of the vibration transmission device with an elastic substance. When the device can be directly mounted, the support base and the housing of the device to be vibrated are sandwiched between elastic materials and fixed to each other. As a result, the sound pressure level can be improved more than before. Also, in the case of the former configuration, a convex portion or a groove portion for positioning the support base is formed on the diaphragm, and a convex portion or a groove portion for positioning the diaphragm is formed on the housing of the vibration transmission device. In the case of the latter configuration, by adopting a configuration in which a convex portion or a groove portion for positioning the support base is formed in the housing of the vibration transmission device, the elastic material can be sandwiched by a double-sided tape or a foam-based material. In addition to facilitating the mechanical strength, it is possible to increase the mechanical strength by fixing the members between them by one of heat staking, press-fitting, and screwing. And improve durability and reliability.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a basic configuration of a vibration actuator according to one embodiment of the present invention.

FIGS. 2A and 2B show a main part configuration in a case where the vibration actuator shown in FIG. 1 is fixed to a housing of a mobile phone terminal as a vibration transmitting body via a diaphragm, and FIG. (B) relates to a partially cut-away side sectional view.

FIG. 3 is a side view showing a structure of a double-sided tape used in the vibration actuator shown in FIG.

FIG. 4 is a graph showing a comparison of the characteristics of the sound pressure level with respect to the frequency of the vibration actuator described in FIG. 2 and the vibration actuator described in FIG.

FIG. 5 is a side sectional view showing a basic configuration of a conventional vibration actuator.

6 (a) is a plan view showing a main part configuration in a case where the vibration actuator shown in FIG. 5 is used to fix to a housing of a mobile phone terminal as a vibration transmission body via a diaphragm. (B) relates to a partially cut-away side sectional view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Yoke 2 Permanent magnet 3 Plate 4 Central axis 5 Coil 6 Damper 6a Outer peripheral part 7 Support base 8,18 Diaphragm 9,19 Mobile phone terminal housing 10,11 Adhesive 12,13 Double-sided tape 15 Base material 16 Adhesive 18a, 19a Positioning convex

Claims (7)

[Claims] A magnetic circuit is movably supported by a central shaft mounted on a support base via an elastic damper, and is positioned and mounted on a peripheral edge of an outer peripheral portion of the damper to form a gap in the magnetic circuit. The coil and the magnetic circuit are driven by the input of the electric signal to the coil provided in the
Further, in a vibration actuator that can be attached to an external vibration transmission device via a vibration plate, at least one of between the support base and the vibration plate and between the vibration plate and the housing of the vibration transmission device. A vibration actuator characterized by being mounted and fixed by being sandwiched between elastic materials. 2. The vibration actuator according to claim 1, wherein the vibrating plate is formed with a convex portion or a groove for positioning the support table, and the vibrating plate is positioned on a housing of the vibrated transmission device. A vibrating actuator having a convex portion or a groove portion formed thereon. 3. A magnetic circuit movably supported by a central shaft mounted on a support base via an elastic damper, and is positioned and mounted on a peripheral edge of an outer peripheral portion of the damper to form an air gap in the magnetic circuit. The coil and the magnetic circuit are driven by the input of the electric signal to the coil provided in the
Further, in a vibration actuator which can be directly mounted on an external vibration transmission device, the vibration is characterized in that the support is mounted and fixed between an elastic substance between the support base and the housing of the vibration transmission device. Actuator. 4. The vibration actuator according to claim 3, wherein a projection or a groove for positioning the support table is formed in a housing of the vibration transmission device. 5. The vibration actuator according to claim 1, wherein the elastic material is provided for fixing between members by any one of heat caulking, press fitting, and screwing. Vibration actuator. 6. The vibration actuator according to claim 5, wherein said elastic substance is a double-sided tape. 7. The vibration actuator according to claim 5, wherein the elastic substance is a foam-based material.