JP2003018686A - Speaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high performance small speaker. SOLUTION: The speaker comprises a magnetic circuit formed of a yoke (11), a permanent magnet (12) and a plate (13), a voice coil (14) disposed in an air gap formed between the yoke and the plate of the magnetic circuit, and a sub-panel (15) for holding the voice coil. The sub-panel (15) is secured to a diaphragm also serving as the surface protective plate of a display and the plate (13) of the magnetic circuit is coupled with the sub-panel (15) through a damper (16).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker, and more particularly to a small speaker suitable for application to a small electronic device such as a mobile phone.

[0002]

2. Description of the Related Art A speaker installed in a mobile phone or the like is required to have high performance and a small size. Japanese Unexamined Patent Application Publication No. 11-331969, which is related to the applicant's earlier application, discloses a speaker that is downsized by using a display panel as a diaphragm. Further, Japanese Patent Application Laid-Open No. 2000-334378 discloses a technique for achieving miniaturization by forming a spiral damper also serving as a diaphragm inside a magnetic circuit.

[0003]

In the speaker according to the prior application of the present applicant, since the yoke of the speaker is fixed to the display panel which also serves as the diaphragm, it is not always sufficient in terms of electric / acoustic conversion efficiency. I can't say. In addition, JP-A-200
The speaker disclosed in Japanese Patent Laid-Open No. 0-334378 also has a problem in electrical / acoustic conversion efficiency because the diaphragm for generating sound also serves as a damper. Therefore, one object of the present invention is to provide a small speaker which is small in size and has high electric / acoustic conversion efficiency.

[0004]

A speaker of the present invention for solving the above-mentioned problems of the prior art is formed between a magnetic circuit including a yoke, a permanent magnet and a plate, and the yoke and the plate of the magnetic circuit. The voice coil is provided in a void, and a sub-panel that holds the voice coil is provided. The sub-panel is fixed to the vibrating plate that also serves as the surface protection plate of the display device, and the plate of the magnetic circuit and the sub-panel are connected by the damper, so that the sub-panel is small and high in electrical / acoustic conversion efficiency. It is configured to realize a speaker.

[0005]

According to a preferred embodiment of the present invention, a damper is fitted in a groove or an opening formed in a plate to increase its thickness and enhance its function as a damper. Is configured.

According to another preferred embodiment of the present invention,
The yoke is fixed not to the surface protection plate but to the frame body surrounding the surface protection plate with the holding tool interposed therebetween, so that a small speaker with higher electric / acoustic conversion efficiency is realized.

According to still another preferred embodiment of the present invention, the surface protection plate of the display device is supported by a frame surrounding the surface protection plate via a soft elastic body, so that the vibration plate It is configured so that efficient excitation is performed.

According to still another preferred embodiment of the present invention, by making the magnetic circuit and the voice coil rectangular, it is possible to realize high space utilization efficiency and simplification and cost reduction of the structure. It is configured.

According to still another preferred embodiment of the present invention, the voice coil has a bobbin-less structure to improve the magnetic flux density so that a large sound output and a high electric / acoustic conversion efficiency are realized. Is configured.

According to still another preferred embodiment of the present invention, the display device is configured to be a liquid crystal display device of a mobile phone.

[0011]

FIG. 1 is a plan view (A) showing a structure of a speaker of an embodiment of the present invention together with a mobile phone in which the speaker is installed, a side perspective view (B) and a partially enlarged sectional view of a speaker (C). Is. The mobile phone P includes a key input section K and a display section D. The display section D for displaying a message is composed of a liquid crystal display device, and a hard surface protection plate S made of transparent glass or plastic is installed to protect the liquid crystal display device. This hard surface protection plate S is used as a diaphragm of the speaker of this embodiment, and its end portion is held while a soft elastic body U is interposed at the peripheral portion of a case formed of a hard material such as resin. Has been done.

As shown in a partially enlarged cross-sectional view (C), the speaker 10 has a substantially L-shaped attachment 16 made of a hard material such as resin or metal on the peripheral portion of the case of the mobile phone P. Fixed. The speaker main body portion excluding the fixture 16 is further enlarged to show a plan view of FIG. 2 (A).
And a cross-sectional view (B). The main body of the speaker includes a yoke (outer yoke) 11, a magnet 12, a plate (inner yoke) 13, a voice coil 14, a sub panel 15, and a damper 16.

The magnetic circuit composed of the yoke 11, the magnet 12 and the plate 13 has a rectangular shape. The voice coil 14 arranged in the space formed between the yoke 11 and the plate 13 has a rectangular shape according to the shape of the space. By using the rectangular voice coil 14 as described above, the voice coil is provided in the rectangular space formed at the end portion of the rectangular surface protection plate S which is also used as the vibrating plate with high space utilization efficiency. Can be placed at.

As a result, a simple and inexpensive structure can be realized as compared with the case where a plurality of circular voice coils are arranged side by side in the same rectangular space. Further, the voice coil 14 has a bobbin-less voice coil structure that does not use a winding frame, so that the size of the void is reduced by the thickness of the bobbin. As a result, a high magnetic flux density can be realized, and sufficient volume and high electric / acoustic conversion efficiency can be realized in spite of the small size.

The upper end of the voice coil 14 is directly fixed to the back surface of the sub-panel 15 via an adhesive layer. The sub-panel 15 is connected to the plate 13 via a damper 16. That is, the upper surface of the damper 16 is bonded and fixed to the bottom surface of the sub-panel 15, and the damper 1
The bottom of 6 is fitted and bonded in the opening formed in the plate 13. The damper 16 is made of a relatively soft elastic material such as urethane foam, and mainly damps and suppresses unnecessary low-frequency components of vibrations excited by the sub-panel 15.

As the damper 16, for example, urethane foam sold under the trade name of "Polon" by Inoac Corporation is suitable because it has a small residual compression strain and is excellent in heat resistance. By thus forming the opening in the plate 13 and increasing the thickness of the damper 16, the function as a damper is improved. The thickness of the damper can also be increased by forming a groove instead of the opening.

The sub-panel 15 has a holding mechanism for directly holding the voice coil 14 without interposing a bobbin, and a surface of the display portion D of the mobile phone P which utilizes the vibration generated by the voice coil 14 as the diaphragm of the speaker. It also has the function of a vibration transmission mechanism that transmits to the protective plate S. Further, as shown in FIG. 3, the sub-panel 15 also has a function of a terminal plate for installing a lead wire terminal (not shown) connected to the voice coil 14 at the right end portion.

FIG. 3 is a plan view (A) and a sectional view (B) showing the structure of a speaker of another embodiment of the present invention. This speaker is also fixed to the mobile phone shown in FIG. 1 via a substantially L-shaped fixture inside the lower end portion of the display portion of the mobile phone, as in the case shown in FIG. Therefore,
The same components as those shown in FIGS. 1 and 2 are designated by the same reference numerals.

This embodiment differs from the embodiment of FIG. 1 in that
The damper 16 is composed of a flat plate-shaped central portion 16a held in the central portion of the plate 13 and a wave-shaped connecting portion 16b connecting the central portion 16a to the inner peripheral edge portion of the sub-panel 15. . The damper 16 is preferably formed integrally with the sub-panel 15, and as a material thereof, an elastomer AR (a product of Aron Kasei Co., Ltd.) having appropriate elasticity and excellent in temperature change and weather resistance is suitable. A cylindrical protrusion formed on the back surface of the central portion 16a is fitted into a circular groove formed on the surface of the plate 13 and is bonded to the damper 16 so that the damper 16 is attached to the plate 1.
3 is firmly connected.

The case where the speaker of the present invention is attached to a mobile phone has been described above. However, the speaker of the present invention can be applied not only to the mobile phone but also to other appropriate small-sized portable electronic device or an appropriate stationary electronic device.

[0021]

As described in detail above, in the speaker of the present invention, the sub-panel is fixed to the diaphragm which also serves as the surface protection plate of the display device, and the gap between the magnetic circuit plate and the sub-panel is adjusted by the damper. Since they are connected to each other, there is an effect that a small-sized speaker with high sound generation efficiency is realized.

Further, according to the preferred embodiment of the present invention, since the yoke is fixed not to the surface protection plate but to the frame surrounding the same with the holding tool interposed, the sound generation efficiency is further improved. It is possible to realize a high-performance compact speaker.

According to another preferred embodiment of the present invention,
Since the surface protection plate of the display device is supported by the frame surrounding the surface protection plate via the soft elastic body, it is possible to efficiently excite the diaphragm.

According to still another preferred embodiment of the present invention, the magnetic circuit and the voice coil are formed in a rectangular shape to enhance space utilization efficiency, and the voice coil has a bobbinless structure to improve the magnetic flux density. Because of the structure, it is possible to realize a simple structure, low cost, high output and high conversion efficiency.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a speaker according to an embodiment of the present invention together with a configuration of a mobile phone in which the speaker is installed.

2 is a plan view (A) and a cross-sectional view (B) showing an enlarged main body portion of the speaker of the embodiment of FIG. 1. FIG.

FIG. 3 is a plan view (A) and a sectional view (B) showing a configuration of a main body of a speaker according to another embodiment of the present invention.

[Explanation of symbols]

10 Speaker 11 Yoke 12 Magnet 13 Plate 14 Voice Coil 15 Sub-panel 16 Damper P Mobile Phone D Display of Mobile Phone S Display Protection Plate of Mobile Phone Display (also acts as Speaker Diaphragm) K Key Input of Mobile Phone

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04R 9/04 104 H04R 9/04 104 105 105B (72) Inventor Yoshiro Okawa 5-17 Futako, Takatsu-ku, Kawasaki-shi, Kanagawa -1 Incorporated in Authentec Co., Ltd. (72) Inventor Tatsuo Yoshida 1-5-1 Higashirokujo Minami, Bibai City, Hokkaido 1-5-1 F-Term in Trimtech Co., Ltd. (Reference) 5D012 BB05 CA04 CA07 GA01 5D016 AA04 EC10 FA01 5D017 AE21 AE29 5K023 AA07 BB03 EE07 HH07

Claims (8)

[Claims] 1. A magnetic circuit composed of a yoke, a permanent magnet and a plate, a voice coil arranged in an air gap formed between the yoke and the plate of the magnetic circuit, and a voice coil held by the voice coil. In the speaker, the sub-panel is fixed to a diaphragm that also serves as a surface protection plate of the display device, and the plate of the magnetic circuit and the sub-panel are connected by a damper. Speaker. 2. The speaker according to claim 1, wherein the damper is fitted in a groove or an opening formed in the plate. 3. The speaker according to claim 1, wherein the sub panel and the damper are integrally formed. 4. The speaker according to claim 1, wherein the yoke is fixed to a frame body surrounding the surface protection plate with a holding tool interposed. 5. The speaker according to claim 1, wherein the surface protection plate of the display device is supported by the frame body through a soft elastic body. 6. The speaker according to claim 1, wherein the magnetic circuit and the voice coil have a rectangular shape. 7. The speaker according to claim 1, wherein the voice coil has a bobbinless structure. 8. The speaker according to claim 1, wherein the display device is a liquid crystal display device of a mobile phone.