JPH0738990A - Speaker diaphragm - Google Patents

Abstract

(57) [Abstract] [Purpose] For a speaker diaphragm used in various audio equipment, which can solve the problems of large distortion, poor heat resistance and weather resistance, and can exhibit excellent performance. The purpose is to provide a diaphragm. [Structure] By using a natural silk fiber cloth as the base material of the speaker diaphragm 1 and coating the surface with a heat-crosslinking type resin, the internal loss of the base material is increased, so that the distortion is reduced and the heat resistance is improved. And weather resistance can be improved.

Description

Detailed Description of the Invention

[0001]

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

[0002]

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

FIG. 4 is a cross-sectional view showing the structure of a conventional speaker diaphragm. The material is a metal such as aluminum, titanium or the like, or a polymer material such as polyarylate (PA) or polyethylene terephthalate (PET), and the like. For example, chemical fibers such as nylon and polyester are impregnated with a phenolic resin for shape retention, and then coated with rubber latex such as SBR and NBR. These materials have a semicircular cross section using a molding die. The speaker diaphragm 2 thus formed was configured.

[0004]

However, in the above-mentioned conventional configuration, when a metal is used as the material of the diaphragm 2 for the speaker, the rigidity of the diaphragm becomes high and the reproduction of higher frequencies is possible. There is a problem that the specific gravity is high, the sound pressure in the output sound pressure frequency characteristic of the speaker is low, the internal loss is low, the distortion is large, and the cost is the highest.

Further, when a polymer material is used, there is a problem that the vibration plate is low in rigidity and reproduction in a high frequency range cannot be performed, and the adhesiveness is poor, resulting in poor quality.

Further, when a base material coated with a rubber latex after impregnating a chemical fiber with a phenol resin is used, reproduction in a high range cannot be performed due to low rigidity, and high heat resistance is low. Since it cannot be used outdoors or in vehicles where reliability is required, and because it is impregnated with a large amount of phenol resin to prevent deformation due to humidity, there is a problem that a hard characteristic sound of the phenol resin is generated during sound reproduction. It was

It is an object of the present invention to solve the above-mentioned conventional problems and provide a speaker diaphragm capable of exhibiting excellent speaker performance.

[0008]

Means for Solving the Problems In order to solve the above problems, the present invention provides a chlorosulphonated polyethylene emulsion in which a natural silk fiber cloth is impregnated with a phenol resin on one side or both sides and one side or both sides is a heat-crosslinkable resin. Is to be coated many times and the base material is heat-molded into a predetermined shape to form a speaker diaphragm.

[0009]

[Function] By using natural silk fiber as the base material of the speaker diaphragm, the internal loss of silk fiber is much higher than that of metal materials, polymer materials, chemical fiber materials, etc. Becomes Also, by coating the surface of silk fiber with a heat-crosslinking resin, reliability such as heat resistance, weather resistance, and moisture resistance is greatly improved, and it can be used not only indoors but also outdoors and in-vehicle. Becomes Further, since the impregnation amount of the phenol resin can be reduced by improving the heat resistance, it is possible to reproduce clear sound quality without characteristic sound.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A speaker diaphragm according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing the structure of a speaker diaphragm according to the present invention, in which one side of 13 silk fibers (weight per unit area of about 48 g / m ² ) is coated with a phenol resin having a solid content of about 20% for shape retention. It was impregnated with an absolute dry weight of about 5 g / m ² , and a chlorosulphonated polyethylene resin having a viscosity of about 150 CPS and a solid content of about 20% was added to 3 parts.
Coated twice, coating weight is about 35g / m ²
Became.

The physical properties of the coating material are shown in (Table 1).

[0012]

[Table 1]

The conventional product shows the data of SBR resin, and it can be seen that the product of the present invention has improved tensile strength and hardness.

The heat resistance of the above coating material is shown in FIG.
The weather resistance is shown in FIG. 3, and it can be seen from FIGS. 2 and 3 that the heat resistance and the weather resistance are greatly improved as compared with the conventional SBR resin.

The above-mentioned substrate was molded at a molding temperature of 190 ° C. for a molding time of 15 sec to form a semi-circular cross section shown in FIG. With this configuration, the internal loss of the base material is high and the heat resistance of the resin is high, so the impregnated amount of the phenol resin for molding and holding can be reduced. It is possible to achieve clear sound quality.

[0016]

As described above, since the speaker diaphragm according to the present invention is configured, it is possible to realize a clear sound quality without eigen sound, and to improve the physical properties due to a special environment such as heat resistance and weather resistance. It is possible to reduce the rate of change, and it is possible to use it not only for indoor use but also for outdoor use, in-vehicle use, etc., which is of great industrial value.

[Brief description of drawings]

FIG. 1 is a cross-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 the speaker diaphragm according to the example.

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

FIG. 4 is a cross-sectional view showing a configuration of a conventional speaker diaphragm.

[Explanation of symbols]

 1 diaphragm

Claims (1)

[Claims] 1. A natural silk fiber cloth is impregnated with a phenol resin on one or both sides, and one or both surfaces of the natural silk fiber cloth is coated with an emulsion of a chlorosulfonated polyethylene resin a number of times, and the base cloth is heat-molded into a predetermined shape. A diaphragm for a speaker.