JP2003299184A - Diaphragm integrated with coil and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a diaphragm integrated with coil for a plane speaker which is small-sized, thin, high-performance, and high-reliability. <P>SOLUTION: The diaphragm integrated with coil for a plane speaker has a coil 12a and pieces of distributing wires 12b on the surface of a film 11 to be a diaphragm, and is provided with a plurality of pieces of distributing wires 12b for causing a current to flow in the coil 12a. Consequently, the plane speaker keeps operating, even if a few out of the pieces of distributing wires 12b are broken. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil-integrated diaphragm having a coil on the surface of the diaphragm and a method for manufacturing the same, and more particularly to a coil-integrated diaphragm for a flat speaker.

[0002]

2. Description of the Related Art Conventionally, a speaker is generally formed after a diaphragm and a coil are separately formed.
However, since a coil-integrated diaphragm in which a coil is directly formed on the surface of the diaphragm has been proposed, a flat speaker can be realized. The realization of this flat speaker has greatly contributed to downsizing of home audio products and diversification of the design of the products.

Furthermore, due to the widespread use of mobile phones,
The demand for small speakers is increasing. Although a display screen is mounted on a mobile phone, in recent years, it has been required to increase the size of the display screen. For this reason, the portion of the mobile phone assigned to the speaker is becoming smaller, and there is an urgent need to further reduce the size and thickness of the speaker. In addition, the speaker of the mobile phone needs to support various ring tones, and the speaker has a small size,
Not only thinning is required, but high characteristics such as ensuring a wide range of tone range characteristics are required.

FIG. 7 is a view showing a conventional coil-integrated diaphragm used for a flat speaker for a mobile phone, for example. In this coil-integrated diaphragm, a coil 72 is formed on a film 71 serving as a diaphragm. This coil 72
Is connected to an external sound source device by an external wiring 77, and when an electric signal is sent, the film 71 vibrates and a sound is generated. FIG. 8 is a diagram showing another conventional coil-integrated diaphragm. In this coil-integrated diaphragm, a coil 82a and a wiring 82b are formed on a film 81 serving as a diaphragm, and the wiring 82b is directly connected to the coil 82a.
When an electric signal is applied to the coil 82a, the film 81 vibrates and a sound is generated.

[0005]

However, in the conventional coil-integrated diaphragm shown in FIG. 8, the coil 82a and the wiring 82b are provided.
Since it is formed on the same film 81, the wiring 82b may be broken due to the vibration of the film 81 when a sound is emitted, and it is difficult to say that the durability is good. Therefore, in the conventional flat speaker for mobile phones, considering the durability of the flat speaker, as shown in FIG.
The wiring 77 for sending an electric signal to the coil 72 has to be attached separately. However, in this coil-integrated diaphragm, the wiring 77 connected to the coil 72 is used.
Since it is an external speaker, it was not easy to make it smaller and thinner as a flat speaker.

In view of the above points, the present invention provides a coil-integrated diaphragm having a small size and a thin structure, which is excellent in durability without the possibility of disconnection of wiring and loss of conduction. Is an issue.

[0007]

In order to solve the above problems and achieve the object of the present invention, the coil-integrated diaphragm according to claim 1 of the present invention is connected to the coil and the coil on the surface of the diaphragm. A coil-integrated diaphragm having wiring formed thereon, wherein a current path of the wiring is divided into a plurality of parts. The coil-integrated diaphragm according to claim 2,
The coil-integrated diaphragm according to claim 1, wherein a photoresist having a coil pattern and a wiring pattern is formed on a substrate, and a conductor serving as a coil and a conductor serving as a wiring are formed in an opening of the photoresist by a plating method. It is characterized by being manufactured by a growing method. The method for manufacturing a coil-integrated diaphragm according to claim 3, wherein the coil and the wiring connected to the coil are formed on the surface of the diaphragm, and the current path of the wiring is provided. Forming a photoresist of a coil pattern and a wiring pattern on a substrate so that the conductor is divided into a plurality of parts, and a conductor to be the coil and a conductor to be the wiring in the opening of the photoresist formed by a plating method. And a step of growing the.

As described above, in the coil-integrated diaphragm in which the coil and the wiring are formed on the surface of the diaphragm, by providing a plurality of wires to the coil on the diaphragm, disconnection of several wires occurs. However, it was possible to maintain good continuity and solve the problem of the flat speaker as described above.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is a diagram showing an embodiment of a coil-integrated diaphragm of the present invention. FIG. 2 is a view showing a cross section taken along a chain line (ab) in FIG. As shown in FIG. 1 and FIG. 2, the coil-integrated diaphragm of the present invention has a coil 1 on a film 11 serving as a diaphragm.
2a and a plurality of (10) wirings 12b are formed, and the wirings 12b are directly connected to the coil 12a.
When an electric signal is applied to the coil 12a, the film 11 vibrates and a sound is generated.

The number of wires directly connected to the coil of the coil-integrated diaphragm of the present invention may be greater than the number of breaks expected to occur, and is preferably twice the number of breaks expected to occur. The above number is enough. Further, the thickness of the wiring on the diaphragm of the coil-integrated diaphragm of the present invention is preferably thick in order to maintain the strength of the wiring, but if it is too thick, vibration is hindered. Therefore, the preferable range of wiring thickness is 2
0 μm to 250 μm, more preferably 30 μm
It is m-130 micrometers.

The metal forming the coil and wiring of the coil-integrated diaphragm of the present invention may be any metal that can be produced by the plating method, and among them, copper is a suitable material. However, the materials of the coil and the wiring of the coil-integrated diaphragm of the present invention may be the same or different. The coil and the wiring of the coil-integrated diaphragm of the present invention are formed by plating, but they may be formed by etching.

Further, a film having a high rigidity is suitable for the film (insulating film) of the coil-integrated diaphragm of the present invention, and the diaphragm for a speaker is such that the center of the diaphragm is hard and the periphery is soft. It is even better to use a material whose peripheral portion can be flexibly processed by firing or the like so as to be ideal. Specific examples include acrylic films and imide films. Further, the material of the photoresist forming the coil pattern and the wiring pattern of the coil-integrated diaphragm of the present invention may be any material that can be patterned by the photolithography method.

Next, a method of manufacturing the coil-integrated diaphragm of the present invention will be described. First, the thickness of the diaphragm 10
One side of the μm acrylic film 11 is roughened by hitting with electrons so that the adhesion of the plating is increased (corona treatment). The surface treatment method of the film may be such that the adhesion of the plating is increased by roughening the film surface, etc., a method by corona treatment, a method of dipping in an acid or the like, a method of physically polishing the film , Etc. are suitable. Next, a photoresist (negative resist) having one coil pattern and ten wiring patterns is formed on the surface subjected to the corona treatment by a photolithography method using a photomask.

Further, the surface on which the photoresist is formed is subjected to electroless copper plating to deposit a copper layer having a thickness of 1 μm, and then the photoresist is removed with a release agent.
Next, for copper deposited in the photoresist opening after the photoresist is stripped, electrolytic copper sulfate plating treatment is performed,
The copper is grown to a thickness of 25 μm to form a coil 12a and a wiring 12b made of copper. Finally, a coil-integrated diaphragm as shown in FIGS. 1 and 2 is produced by cutting into an appropriate size so that it can be easily used for a flat speaker. This coil-integrated diaphragm directly plated the film without using an adhesive, so there is less expansion and contraction and distortion caused by the use of an adhesive, and the number of manufacturing processes is less than other processes. Is preferred.

Next, another embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a diagram showing another embodiment of the coil-integrated diaphragm of the present invention. FIG. 4 is a view showing a cross section taken along a chain line (cd) in FIG. As shown in FIGS. 3 and 4, in the coil-integrated diaphragm of the present invention, an adhesive layer 33 is laminated on a film 31 which serves as a diaphragm, and the coil 32 a and a plurality of (10) layers are formed on the adhesive layer 33. Book) wiring 32b is formed. The adhesive layer 33 is laid only under the coil 32a and the wiring 32b, and the wiring 32b is directly connected to the coil 32a.

Next, a method of manufacturing the coil-integrated diaphragm of the present invention will be described. First, after zincating treatment (zincate treatment) on one surface of an aluminum substrate, copper pyrophosphate plating treatment is performed to deposit a copper layer having a thickness of 1 μm. Any substrate can be used as long as it can be removed after the resist pattern is formed, and an aluminum substrate, a copper substrate and the like are preferable because they can be removed by etching with an acid-based solution.
Next, a photoresist (negative resist) having one coil pattern and ten wiring patterns is formed on the surface on which the copper layer has been deposited, by a photolithography method using a photomask. Then, electrolytic copper sulfate plating is performed on the surface on which the photoresist is formed to deposit copper in the photoresist opening. The deposited copper is grown to a thickness of 25 μm, and the copper coil 3
2a and wiring 32b are formed.

Further, after removing the photoresist with a release agent, an epoxy adhesive 33 is pattern-printed on the surface portions of the coil 32a and the wiring 32b, and an acrylic film 31 having a thickness of 10 μm to be a vibration plate is adhered thereto. .
The thickness of the adhesive layer is preferably 40 μm or less, more preferably 10 μm or less, from the viewpoint of not impairing the vibration easiness of the vibration plate. Agents are suitable. In addition, the expansion / contraction rate of the film that becomes the diaphragm after the adhesive is cured is 1/1 in that it does not impair the ease of vibration of the diaphragm.
It is preferably 000 or less. Finally, after removing only the aluminum substrate and the copper layer on the aluminum substrate that was deposited first by etching, it was cut into a suitable size for easy use as a flat speaker, and as shown in FIGS. 3 and 4. A coil-integrated diaphragm is manufactured.

Next, still another embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a diagram showing another embodiment of the coil-integrated diaphragm of the present invention. FIG. 6 is a view showing a cross section taken along a chain line (e-f) in FIG. As shown in FIGS. 5 and 6, in the coil-integrated diaphragm of the present invention, the adhesive layer 53 and the resin layer 54 are laminated on the film 51 to be the diaphragm, and the photoresist 56 is laid on the resin layer 54. Has been. A coil 52a and a plurality of (10) wires 52b are formed in the opening of the photoresist 56. The wiring 52b is the coil 52a
Is directly connected to the coil 52a and the wiring 52
A resin layer 55 is laid on top of b.

Next, a method of manufacturing the coil-integrated diaphragm of the present invention will be described. First, after zincating treatment (zincate treatment) on one surface of an aluminum substrate, copper pyrophosphate plating treatment is performed to deposit a copper layer having a thickness of 1 μm. Any substrate can be used as long as it can be removed after the resist pattern is formed, and an aluminum substrate, a copper substrate or the like is preferable because it can be removed by etching with an acid-based solution. next,
For the surface on which the copper layer is deposited, using a photomask,
A photoresist (negative resist) 56 having one coil pattern and ten wiring patterns is formed by a photolithography method. Next, electrolytic copper sulfate plating is performed on the surface on which the photoresist 56 is formed to deposit copper in the photoresist opening. The deposited copper is grown to a thickness of 15 μm to form a coil 52a and a wiring 52b made of copper.

Next, with respect to the surfaces of the coil 52a, the wiring 52b and the photoresist 56, an acrylate resin 54 is formed.
Is entirely printed by a screen printing method, and further, an epoxy adhesive 53 is entirely printed on the same surface by a screen printing method, and an acrylic film 51 having a thickness of 10 μm serving as a vibration plate is adhered thereto. Any resin can be used as long as it can maintain insulation between the conductors forming the coil and the wiring, and an acrylate resin, an epoxy resin, or the like is suitable. The thickness of the adhesive layer to be used is preferably 40 μm or less, more preferably 10 μm or less, from the viewpoint of not impairing the vibration easiness of the diaphragm. A system adhesive or the like is suitable. Further, the expansion / contraction rate of the film that becomes the vibration plate after the adhesive is cured is preferably 1/1000 or less from the viewpoint of not impairing the vibration easiness of the vibration plate.

Further, after removing only the copper layer on the aluminum substrate and the aluminum substrate initially deposited by etching, electrolytic copper sulfate plating is performed on the etched surface to form a photoresist opening. Precipitate copper on.
The deposited copper has a thickness of 15 μm, that is, together with the copper having a thickness of 15 μm deposited in the previous process, the copper is grown again until the total thickness becomes 30 μm to form the coil 52a and the wiring 52b made of copper. Finally, the coil 52
After pattern-printing the acrylate resin 55 on the surface portion of a, it is cut into an appropriate size so that it can be easily used for a flat speaker, and a coil-integrated diaphragm as shown in FIGS. 5 and 6 is produced. In this coil-integrated diaphragm, since the resin layer on the upper part covers only the coil portion, flexibility near the edge of the diaphragm can be maintained, and the diaphragm can obtain good vibration. It is preferable in that it can be done.

When the above-described coil-integrated diaphragm of the present invention was used as a flat speaker, it was practically most used at 50 Hz in all flat speakers.
A flat gain characteristic was obtained in the range from to 2500 Hz. Moreover, even after continuous use for 1000 hours or more, 5 of the 10 wires connected to the coil formed on the film were not cut, and the continuity to the coil was maintained. As described above, the planar speaker using the coil-integrated diaphragm having a plurality of wirings has a small size, a thin shape, a high performance, and can withstand long-time use sufficiently and can be reliable.

On the other hand, a coil-integrated diaphragm having one wiring pattern was produced in the same manner as the embodiment except that the number of wiring patterns was one. When these coil-integrated diaphragms were used as flat speakers, all flat speakers were 50Hz to 2500Hz.
It was possible to obtain a flat gain characteristic in the range up to. However, after 100 hours of continuous use, the wiring connected to the coil formed on the film was cut, and conduction to the coil was not maintained. As described above, the flat speaker having the coil-integrated diaphragm with one wiring cannot obtain sufficient reliability.

[0024]

As described above, according to the present invention, in the coil-integrated diaphragm in which the coil and the wiring are formed on the film serving as the diaphragm, by providing a plurality of wirings directly connected to the coil, Good continuity can be maintained even if several wires are broken, and the flat speaker using the coil-integrated diaphragm maintains small size, thinness, and high performance.
It can be made highly reliable.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a coil-integrated diaphragm of the present invention.

FIG. 2 is a view showing a cross section along a chain line (ab) in FIG.

FIG. 3 is a view showing another embodiment of the coil-integrated diaphragm of the present invention.

FIG. 4 is a view showing a cross section taken along a chain line (cd) in FIG.

FIG. 5 is a view showing another embodiment of the coil-integrated diaphragm of the present invention.

6 is a diagram showing a cross section taken along a chain line (e-f) in FIG.

FIG. 7 is a diagram showing a conventional coil-integrated diaphragm.

FIG. 8 is a diagram showing another conventional coil-integrated diaphragm.

[Explanation of symbols]

11, 31, 51, 71, 81 Film (insulating film) 12a, 32a, 52a, 72a, 82a coil 12b, 32b, 52b, 82b wiring 33, 53 adhesive layer 54, 55 resin layer 56 Photoresist (negative resist) 77 wiring (external)

Continued front page    F-term (reference) 5D012 AA02 BA03 BA05 HA00 HA04                 5D016 AA01 AA04 JA11 JA16

Claims (3)

[Claims] 1. A coil-integrated diaphragm in which a coil and a wire connected to the coil are formed on a surface of the diaphragm, wherein a current path of the wire is divided into a plurality of parts. A coil-integrated diaphragm. 2. A method of forming a photoresist of a coil pattern and a wiring pattern on a substrate and growing a conductor to be a coil and a conductor to be a wiring in an opening of the photoresist by a plating method. The coil-integrated diaphragm according to claim 1. 3. A method of manufacturing a coil-integrated diaphragm in which a coil and a wire connected to the coil are formed on a surface of the diaphragm, wherein a current path of the wire is divided into a plurality of parts. Forming a photoresist of a coil pattern and a wiring pattern on a substrate; and growing a conductor to be the coil and a conductor to be the wiring in an opening of the photoresist formed by a plating method. A method of manufacturing a coil-integrated diaphragm, comprising: