JPH11331966A - Panel speaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a panel type speaker whose profile is made thin and where both front and rear sides are utilized. SOLUTION: This speaker is provided with an exciter 10 having magnetic circuits 12, 13, 14 and a voice coil 11 and with a flat diaphragm 20 whose middle part is coupled with the exciter 10. The exciter 10 is imbedded inside the diaphragm 20 to realize thin profile and to use both front and rear sides.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a panel type loudspeaker, and more particularly to a vibration mode (DM) in which an exciter is embedded in a diaphragm to further reduce the thickness and omnidirectionality in both directions. The present invention relates to a panel type speaker.

[0002]

2. Description of the Related Art Japanese Patent Application No. 9-59 relating to the prior application of the present applicant.
No. 889 discloses a panel-type speaker or a planar speaker having the structure shown in FIG. The panel type speaker 10 includes an exciter (drive unit) 11 including a magnetic circuit and a voice coil, and a disk-shaped diaphragm 12 having a central portion fixed to the exciter 11.

In this panel type speaker 10, an opening 2 is formed in a housing 1 of various electronic devices such as a personal computer, an audio device, and a video device. A cylindrical body 3 is provided at the center of the holding plate 3.
a is formed, and the exciter 11 is held in the cylindrical body 3a by caulking, whereby the exciter 11 is attached to the electronic device. The peripheral portion of the diaphragm 12 is supported by a cushion 3b mounted on the holding plate 3. The panel-type speaker 10 is not rigid in that the diaphragm 12 performs a translational motion in the front-back direction, but performs flexural vibration.
It is also called a (DistributedMode) system or a vibration mode system planar speaker.

[0004]

The panel-type speaker of the prior application described above has a problem that the thickness of the panel speaker is not sufficient because the exciter projects rearward from the rear surface of the diaphragm. This is also because the panel-type speaker of the prior application was supposed to be mounted in the housing of the electronic device. However, this type of panel type speaker is not only used in combination with various electronic devices, but also when it is applied to various fields as a thin panel type speaker independent of this type of electronic device, it is required to further reduce the thickness. Is required. Therefore, one object of the present invention is to further reduce the thickness of this type of panel type speaker.

[0005]

SUMMARY OF THE INVENTION A panel type speaker according to the present invention is a panel type speaker comprising an exciter including a magnetic circuit and a voice coil, and a flat diaphragm having a central portion coupled to the exciter. The exciter is embedded in the inside of the diaphragm, so that the exciter can be reduced in thickness and both front and back surfaces can be utilized.

[0006]

According to a preferred embodiment of the present invention, the exciter includes a sub-panel having a cylindrical side wall surrounding an outer yoke constituting the magnetic circuit and an end face closing one end of the side wall. The inner peripheral surface of an opening formed at the center of the diaphragm is joined to the outer peripheral surface of the side wall of the sub panel, and the rear end surface of the outer yoke is connected to the rear end surface of the side wall of the sub panel via an elastic holding mechanism. The end face of the voice coil is joined to the end face of the sub-panel.

According to a further preferred embodiment of the present invention,
In the elastic holding mechanism, a plurality of peripheral portions are fixed to a rear end surface of a side wall of the sub-panel, and are connected to the peripheral portion through a plurality of arc-shaped notches divided in a circumferential direction. It is a disk-shaped thin plate, and this thin plate is made of a metal plate having a thickness of 1 mm or less. The sub-panel is made of polycarbonate or another resin.

[0008]

FIG. 1 is a plan view (A) of a single exciter constituting a panel-type speaker according to an embodiment of the present invention, and a partial cross-sectional view (B) of a panel-type speaker obtained by combining the exciter and a diaphragm. It is. The panel type speaker of this embodiment has a thickness of 5 mm to 10 m made of styrene foam.
m large-sized rectangular diaphragm 20 and this diaphragm 20
And an exciter 10 embedded in the central part of the exciter. The exciter 10 has a voice coil 11,
Permanent magnet 12, inner yoke 13, outer yoke 1
4, a sub panel 15 and an elastic holding plate 16 are provided.

The diameter of the cylindrical outer yoke 14 is
In this example, it is about 30 mm, and a sub-panel 15 made of polycarbonate is formed outside the outer yoke 14. This sub-panel 15 is
And a thin end surface 15b that closes one end surface of the side wall. The diameter of the side wall 15a of the sub panel 15 is typically about 50 mm, and the outer peripheral surface thereof is fixed to the inner peripheral surface of the diaphragm 20 with an adhesive. The thickness of the thin end surface 15b of the sub panel 15 is about 1 mm, and the front end surface of the voice coil 11 is fixed to this end surface by bonding.

Further, a rear end face of the outer yoke 14 is connected to a rear end face of the side wall 15a of the cylindrical body 15 via an elastic holding plate 16. The elastic holding plate 16 is made of a stainless steel thin plate having a thickness of 0.4 mm. As shown in FIG. 1A, the elastic holding plate 16 forms three arc-shaped notches which are divided in the circumferential direction at a position slightly closer to the center from the periphery of the disk. By 3
It has a structure in which an arc-shaped outer peripheral portion and a disk-shaped central portion are connected by connecting portions 18a, 18b, and 18c having narrow portions.

Openings 17a, 17b and 17c formed at three places around the holding plate 16 are inserted into projections formed at the rear end face of the side wall 15a of the cylindrical body 15, and these places are inserted into the rear end face of the side wall 15a. It is fixed on the top with an adhesive.
The rear end face of the outer yoke 14 is fixed to the disc-shaped central portion of the elastic holding plate 16 with an adhesive. 19a and 19b are electrode terminals to which electric wires connected to the voice coil 11 are connected.

The above description will be summarized with reference to the sectional view of FIG. 1B. The outer yoke 14, the permanent magnet 12, and the inner yoke 13 constituting the exciter 10 will be described.
The side wall 15 of the sub panel 15 is
a, and the front end face of the voice coil 11 is fixed to the thin end face 15 b of the sub panel 15. Therefore, if both the rigidity of the elastic holding plate 16 and the rigidity of the end face 15b are sufficiently large, the voice coil 11 and the outer yoke 14 cannot move relative to each other, and no vibration occurs.

However, in practice, the elastic holding plate 16
The thickness of the metal plate is reduced to about 0.4 mm and the circular arc-shaped notch is formed in the circumferential direction as described above, and the thickness of the polycarbonate is reduced to about 1 mm for the end face 15b of the sub-panel. By doing so, the respective stiffness is reduced to an appropriate value, thereby enabling the relative movement between the voice coil 11 and the outer yoke 14 and generating the accompanying vibration. The elastic holding plate 16 also functions as a damper for attenuating the vibration so that the vibration does not last for an unnecessarily long time.

The vibration in the audible frequency band generated by the movement of the voice coil 11 passes through the outer peripheral surface of the side wall 15a of the sub-panel 15 and an adhesive layer formed outside thereof at an opening formed at the center of the diaphragm 20. The light is transmitted to the inner peripheral surface and transmitted from the central portion toward the peripheral portion of the diaphragm 20. The vibration transmitted to the diaphragm is radiated in both the front and back directions of the diaphragm under substantially the same radiation characteristics. That is, the radiation characteristics of the panel-type speaker are non-directional in both directions of the diaphragm.

The diaphragm 20 is typically several hundred mm × several hundred mm.
The four peripheral portions are held by a frame having a large rigidity while allowing deformation by appropriate bending. The front and back surfaces of the diaphragm 20 are typically covered with paper on which a beautiful painting is printed, and the exciter 10 is completely hidden from the viewer's view. Such speakers are typically used as screens, partitions, hanging signs, etc., and viewers can hear the sound emitted from the speaker as if it were a fantastic sound coming from the world of painting. I feel

[0016]

As described above in detail, the panel type speaker according to the present invention has a structure in which the exciter is embedded in the diaphragm, so that the structure is more thinner than that of the prior art which is mounted behind the diaphragm. Is achieved.

In addition, since the exciter is completely embedded in the diaphragm, the diaphragm can be covered with printed paper such as a picture, so that the exciter can be used as a signboard for advertisement or a hanging signboard. Is enlarged.

Further, by completely embedding the exciter in the diaphragm, the omnidirectionality of the front and back sides becomes more remarkable, and the application to a standing signboard for advertisement or a hanging signboard is expanded.

Further, since the panel type speaker of the present invention can be easily assembled as an exciter alone including the support of the magnetic circuit, it can be shared with panel type speakers of different applications, thereby improving productivity and manufacturing. This is advantageous in terms of cost.

[Brief description of the drawings]

FIG. 1 is a plan view (A) of an exciter alone constituting a panel-type speaker according to an embodiment of the present invention, and a partial cross-sectional view (B) of a panel-type speaker composed of the exciter and a diaphragm.

FIG. 2 is a cross-sectional view illustrating a configuration of a panel-type speaker according to the related art.

[Description of Signs] 10 Exciter 11 Voice coil 12 Permanent magnet 13 Inner yoke 14 Outer yoke 15 Sub panel 15a Side wall 15b End face 16 Elastic holding plate 20 Diaphragm

Claims (6)

[Claims] 1. A panel-type speaker comprising: an exciter including a magnetic circuit and a voice coil; and a flat diaphragm having a central portion coupled to the exciter, wherein the exciter is embedded inside the diaphragm. A panel-type speaker. 2. The sub-panel according to claim 1, wherein the exciter includes a sub-panel having a cylindrical side wall surrounding the external yoke constituting the magnetic circuit and an end face closing one end of the side wall. An inner peripheral surface of an opening formed in the central portion of the diaphragm is coupled to a surface of the diaphragm, and a rear end surface of the external yoke is coupled to a rear end surface of a side wall of the sub panel via an elastic holding mechanism. A panel-type speaker, wherein a tip surface of the voice coil is coupled to the speaker. 3. The elastic holding mechanism according to claim 2, wherein a plurality of peripheral portions are fixed on a rear end surface of a side wall of the sub-panel and a plurality of circumferentially divided peripheral portions are formed on the peripheral portion. A panel-type speaker which is a disc-shaped thin plate which is connected while interposing an arc-shaped notch. 4. A panel-type speaker according to claim 3, wherein said disc-shaped thin plate is a metal plate having a thickness of 1 mm or less. 5. A panel type speaker according to claim 2, wherein said sub-panel is made of polycarbonate or another resin. 6. A panel-type speaker according to claim 1, wherein a peripheral portion of said diaphragm is supported by a frame.