JP3039082B2 - Speaker diaphragm - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diaphragm for a speaker used in various audio equipment.

[0002]

2. Description of the Related Art A conventional speaker diaphragm of this type will be described with reference to the drawings.

FIG. 6 is a perspective view showing the structure of a conventional speaker diaphragm, which is made of a metal such as aluminum or titanium or a polymer material such as polyarylate (PA) or polyethylene terephthalate (PET), and nylon. , A polyester fiber or other chemical fiber impregnated with a phenolic resin for shape retention, and then coated with a rubber-based latex such as SBR or NBR. Thus, the speaker diaphragm 5 was formed.

[0004]

However, in the above-mentioned conventional configuration, when metal is used as the material of the speaker diaphragm 5, the rigidity of the diaphragm is increased, and reproduction of a higher sound range is possible. The specific gravity is high, the sound pressure in the output sound pressure frequency characteristics of the speaker is low, and the distortion is large due to low internal loss, and the cost is the highest. When a polymer material is used, reproduction of a high sound range cannot be performed because the rigidity of the diaphragm is low, and quality is also poor because of poor adhesiveness. When a base material coated with rubber-based latex is used after impregnating a chemical fiber with a phenol resin, high rigidity cannot be reproduced due to low rigidity and high reliability due to low heat resistance. Cannot be used for outdoor or on-vehicle applications as required. Furthermore, since a large amount of phenol resin is impregnated to prevent deformation due to humidity, there is a drawback that a hard inherent sound of the phenol resin is generated during sound quality reproduction.

An object of the present invention is to solve the above-mentioned conventional problems and to provide a speaker diaphragm which can exhibit excellent speaker performance.

[0006]

In order to solve the above-mentioned problems, the present invention provides an amorphous metal layer formed on one or both sides of a chemical fiber by a sputtering method, and a phenol resin impregnated in the substrate. A thermo-crosslinkable resin layer formed by coating one or both surfaces a number of times, and a base plate that is heated and formed into a predetermined shape to form a speaker diaphragm.

[0007]

[Function] As described above, the use of chemical fibers as the base material of the speaker diaphragm makes it possible to reduce distortion because the internal loss of the chemical fibers is much higher than that of metal or polymer materials. In addition, the metal coating on the surface of the chemical fiber increases the rigidity, enabling the reproduction of a higher sound range, and the coating of a thermo-crosslinkable resin provides reliability such as heat resistance, weather resistance, and moisture resistance. The phenolic resin impregnation amount can be reduced by improving the heat resistance, so that clear sound quality with no inherent sound can be achieved. Can be reproduced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A speaker diaphragm according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing the structure of a speaker diaphragm according to the present invention. A titanium metal layer 2 having a thickness of about 1000 ° is provided on one surface of a polyester fiber (having a basis weight of about 45 g / m ² ) by sputtering. After that, the resin was impregnated with a phenol resin having a solid content of about 20% for shape retention at an absolute dry weight of about 5 g / m ² , and was further impregnated with a viscosity of about 1%.
The chlorosulfonated polyethylene resin layer 3 having 50 CPS and a solid content of about 20% was coated three times to form a coating weight of about 35 g / m ² . However, when the substrate was made of a natural fiber (silk: cotton, etc.), the water absorption of the substrate was high, so that the thickness of the titanium layer varied during coating, and the physical properties were not stable.

The physical properties of the above coating agent are shown in Table 1.

[0010]

[Table 1]

The data of the conventional product is the data of the SBR resin.
It can be seen that the tensile strength has been improved. FIG. 2 shows the heat resistance of the coating material, and FIG. 3 shows the weather resistance. Both heat resistance and weather resistance are greatly improved as compared with the conventional SBR resin. Further, the titanium metal layer 2 whose surface is coated by the sputtering method has an amorphous structure. Amorphous is also called an amorphous material, and has the following features as compared with a general metal crystal structure type. (1) High mechanical strength and excellent toughness. (2) It has high hardness. (3) Excellent corrosion resistance.

For this reason, the speaker diaphragm 4 has a structure with high rigidity due to the high internal loss of the polyester fiber as the base material and the surface titanium amorphous coating.

The above base material was formed at a molding temperature of 190 ° C. and a molding time of 15 sec into a semicircular cross section shown in FIG. 1 to form a speaker diaphragm 4. Since the internal loss of the base material is high and the heat resistance of the resin is high, the impregnation amount of the phenol resin for holding the molded article can be reduced, so that the hard inherent sound of the phenol resin can be reduced. FIG. 4 shows a third-order distortion characteristic in an output sound pressure frequency characteristic of a speaker using the present invention and a conventional speaker diaphragm. From this figure, it can be seen that the third-order distortion has been reduced by 10 dB. Furthermore, due to the high rigidity of the coating layer on the surface, reproduction up to a higher frequency range was possible. FIG. 5 shows the output sound pressure frequency characteristics of the speaker using the speaker diaphragm according to the present invention and the conventional speaker diaphragm. From this figure, it was found that the high frequency limit frequency was improved by 15%, and clear sound quality was also realized.

The metal layer 2 may be made of any material other than titanium, as long as it is a metal that becomes amorphous.

[0015]

As described above, since the speaker diaphragm according to the present invention is constructed, it is possible to realize a clear sound quality without a peculiar sound, and further, it is possible to expand a high sound range by a surface coating. Since the rate of change in physical properties due to special environments such as heat resistance and weather resistance can be reduced, it can be used not only for indoor use but also for outdoor and in-vehicle applications, resulting in an industrial value. Is a great thing.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a speaker diaphragm according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram showing heat resistance of a coating agent used for a diaphragm for a speaker according to the example and a conventional example.

FIG. 3 is a characteristic diagram showing weather resistance of a coating agent used for a speaker diaphragm according to the embodiment and a conventional example.

FIG. 4 is a diagram showing a third-order distortion characteristic in an output sound pressure frequency characteristic of a product using the speaker diaphragm according to the embodiment and the conventional example.

FIG. 5 is an output sound pressure frequency characteristic diagram of a product using the speaker diaphragm according to the embodiment and the conventional example.

FIG. 6 is a sectional view of a conventional speaker diaphragm.

[Explanation of symbols]

 1 polyester fiber 2 metal layer 3 chlorosulfonated polyethylene resin layer

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04R 7/02

Claims (1)

(57) [Claims] An amorphous metal layer provided on one or both sides of a chemical fiber by a sputtering method, a phenol resin impregnated on the substrate, a thermo-crosslinkable resin layer formed by coating many times, A speaker diaphragm formed by heating a base fabric into a predetermined shape.