JPH11275845A - Vibrating actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibrating actuator which prevents sound pressure from lowering markedly, even if force is applied to an outside box and vibration is suppressed. SOLUTION: A coil 5 is arranged in the gap of a magnetic circuit formed using a permanent magnet 2, and an electric signal is inputted to this coil to have vibrators 5, 6, 9, 10 vibrated. An additional board 7 having a larger outside diameter is fixed to the vibrators 5, 6, 9, 10, and a protrusion 14 is formed in the protruded-outside part of this additional board 7 is brought into contact with an outside box 15, and the vibration of the vibrators 5, 6, 9, 10 is transmitted to the box 15.

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 such as a portable telephone and has a function of generating a ringing sound, voice or vibration.

[0002]

2. Description of the Related Art A vibration actuator of this type is described, for example, in Japanese Patent Application No. 8-324997 (vibration actuator for pager). As shown in FIG. 4, the vibration actuator includes a magnetic circuit including a permanent magnet 2, a yoke 1, and a plate 3. The magnetic circuit includes a resin damper 8 and a support rubber 12 which is a flexible structure attached to a claw-shaped protrusion 11 provided on a support base 10.
And, it is supported to move up and down flexibly. When a drive current is passed through the coil 5, the magnetic circuit moves up and down in the axial direction, and the vibration is transmitted to an external housing via the outer peripheral portion 6 of the damper 8 and the support base 10. Reference numeral 4 denotes a central axis connecting the yoke 1 and the permanent magnet 2 to the damper 8, and 9 denotes an elastic material for preventing the yoke 1 from directly colliding with the support 10.

[0003]

In the above-described conventional vibration actuator, when a sound is generated, the vibration of an external housing is a main sound source, so that the housing is strongly pressed against an ear or the like. Therefore, when a force is applied to the housing, vibration is suppressed, and as a result, there is a problem that the sound pressure is significantly reduced.

[0004] Therefore, an object of the present invention is to provide a vibration actuator capable of preventing a significant reduction in sound pressure even when vibration is suppressed by the application of a force to an external housing.

[0005]

According to the present invention, there is provided a magnetic circuit constituted by using a permanent magnet, a coil disposed in a gap of the magnetic circuit, and an electric signal input to the coil. In a vibration actuator having a vibrating body that vibrates in accordance with the relative movement of the magnetic circuit and the coil, an additional plate having a large outer diameter fixed to the vibrating body, and an additional plate outwardly from the vibrating body of the additional plate. A vibration actuator is provided, which is provided with a vibration transmission unit interposed between the protruding portion and the external housing and transmitting vibration to the housing.

The vibration transmitting section may be fixed to the additional plate, or may be fixed to the housing.

Preferably, the additional plate projects outward from the vibrating body over the entire circumference, and the vibration transmitting portion is provided corresponding to a portion of the additional plate projecting outward.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vibration actuator according to a first embodiment of the present invention will be described with reference to FIGS.

The vibration actuator shown in FIGS. 1 and 2 is mounted on a mobile communication device such as a mobile phone, and is constituted by sandwiching a disk-shaped permanent magnet 2 between a yoke 1 and a plate 3. Includes a magnetic circuit. The center shaft 4 has a shape like a bolt, penetrates a center hole in the center of the damper 8, and is fitted into the center hole of the magnetic circuit. That is, the magnetic circuit and the damper 8 are controlled by the center shaft 4.
Are positioned coaxially. The damper 8 is formed to have a plurality of spiral shapes so as to flexibly support the magnetic circuit, and integrally has a bobbin 13 that supports the coil 5.

The support base 10 has a plurality of claw-like projections 11 at the outer edge thereof, and a support rubber 12 is attached to the claw-like protrusions 11. The support rubber 12 is assembled so as to flexibly support the magnetic circuit so that the magnetic circuit does not separate from the support base 10.

The elastic member 9 is provided on the yoke 1 so as to prevent the magnetic circuit from colliding with the support 10 and generating a collision sound.
And the support 10 are interposed and adhered to the support 10.

Further, a collision plate 7 as an additional plate having an outer diameter larger than the outer diameter of the support 10 is fixed to the support 10. An annular projection 1 is provided on the outer peripheral edge of the collision plate 7.
4 is provided as a vibration transmission unit. The protrusion 14 is connected to a housing 15 having a sound emission hole 16. Collision plate 7
May have a hole at the center or may be formed integrally with the support 10. The projection 14 does not necessarily have to be annular, and may be provided on the housing 15 side.

When a drive current is applied to the coil 5, the coil 5, the outer peripheral portion 6 of the damper integrated with the coil 5, and the support table 10 vibrate due to the repulsive force of the magnetic circuit flexibly supported by the damper 8 and the supporting rubber 12. , The vibration of the collision plate 7
And causes the collision plate 7 to vibrate.
The housing 15 is also caused to vibrate via. When the frequency of this vibration is from several hundred hertz to several thousand hertz, it becomes a voice, and when it is around 100 hertz, it becomes a vibration notifying of an incoming call. Here, the coil 5, the damper outer peripheral portion 6, the elastic body 9, and the support base 10 are collectively called a vibrator.

When sound is generated, when a force is applied to the housing 15 by an action such as strongly pressing the housing 15 against the ear,
Although the vibration of the housing 15 is suppressed and the sound directly generated from the housing is reduced, even in this case, no force is applied to the collision plate 7, so that the sound due to the vibration of the collision plate 7 is transmitted to the outside through the sound emission hole 16. Convey. Therefore, even if a force is applied to the housing 15, the sound pressure does not significantly decrease.

FIG. 3 shows a second embodiment of the present invention.
The same parts as those of the vibration actuator shown in FIG. 1 and FIG. In the vibration actuator of FIG. 3, the magnetic circuit is flexibly supported only by the damper 19. That is, the support rubber 12 and the support base 10 in the vibration actuator of FIG. 1 are omitted. The collision plate 7 is fixed to the outer peripheral portion 6 of the damper. Therefore, in the vibration actuator of FIG. 3, the coil 5, the damper outer peripheral portion 6, and the elastic body 9 work together as a vibration body.

The outer peripheral portion 6 of the damper and the collision plate 7 may be formed integrally.

[0017]

As described above, according to the present invention, there is provided a structure in which a vibration transmitting portion is interposed between an outwardly protruding portion of an additional plate having a large outer diameter fixed to a vibrating body and an external housing. As a result, it has become possible to provide a vibration actuator that does not lower the sound pressure even when a force is applied to an external housing to suppress vibration.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of a vibration actuator according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the vibration actuator of FIG. 1;

FIG. 3 is a longitudinal sectional view of a vibration actuator according to a second embodiment of the present invention.

FIG. 4 is a partially cutaway perspective view of an example of a conventional vibration actuator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Yoke 2 Permanent magnet 3 Plate 4 Center axis 5 Coil 6 Damper outer peripheral part 7 Collision plate as an additional plate 8, 19 Damper 9 Elastic material 10 Support stand 11 Claw-like projection 12 Support rubber 13 Bobbin 14 Projection (vibration transmission part) 15 Casing 16 Sound emission hole

Claims (4)

[Claims] 1. A magnetic circuit formed by using a permanent magnet, a coil disposed in a gap of the magnetic circuit, and a relative position between the magnetic circuit and the coil according to an electric signal input to the coil. In a vibration actuator having a vibrating body that vibrates in accordance with movement, an additional plate having a large outer diameter fixed to the vibrating body, and a portion of the additional plate protruding outward from the vibrating body and an external housing. And a vibration transmission unit for transmitting vibration to the housing interposed therebetween. 2. The vibration actuator according to claim 1, wherein the vibration transmission section is fixed to the additional plate. 3. The vibration actuator according to claim 1, wherein the vibration transmission unit is fixed to the housing. 4. The additional plate protrudes outward from the vibrating body over the entire circumference, and the vibration transmitting portion is provided corresponding to a portion protruding outward of the additional plate. 4. The vibration actuator according to any one of 3.