JPH08168093A - Diaphragm for speaker - Google Patents

Abstract

PURPOSE: To provide a speaker diaphragm superior in reliability by resolving the problems of edge resonance and f0 reduction of the speaker with respect to the speaker diaphragm used in various sound apparatus. CONSTITUTION: The outer peripheral part of a diaphragm main body 2 is stuck to the inner peripheral part of an edge 1 formed by heating and forming the base material where a woven fabric where phenol fibers are mixed with parapolyamide fibers is coated with a phenol resin and a high polymer resin. Thus, the fitting between the phenol resin coated for the purpose of holding the shape and the phenol fibers is improved, and the adhesion is increased to more integration, and therefore, the internal loss of the base material of the edge 1 is increased to reduce the distortion, and the reduction of the f0 change rate of the speaker is suppressed.

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 half cross-sectional view showing the structure of a conventional speaker diaphragm. Urethane foam or a cotton woven cloth coated with a phenol resin and a polymer resin is heat-formed into a corrugated shape using a molding die. The outer peripheral portion of the diaphragm 8 is fixed to the inner peripheral portion of the edge 7 to form the speaker diaphragm.

FIG. 5 is a half sectional view showing the structure of a conventional speaker diaphragm constructed in the same manner as in FIG.
An example is shown in which the outer peripheral portion of the diaphragm 8 is fixed to the inner peripheral portion of the edge 9 which is heat-molded into a roll shape, and the conventional speaker diaphragm is configured in this manner.

[0005]

However, in the above conventional structure, when urethane foam is used for the edge 7 or the edge 9, the internal loss of the material is high, which is advantageous in terms of the sound quality of the speaker. Since the molding time for molding into a shape is long, the cost is high, and the physical properties are severely deteriorated by ultraviolet rays and humidity, so that the field of use is limited.

Further, when a cotton woven cloth is used for the edge 7 or the edge 9, the cost is low and the deterioration of the physical properties due to ultraviolet rays and humidity is small, so that it can be widely used. There is a problem that the deformation when a large amplitude is applied becomes large, and not only the edge resonance occurs, but also the minimum resonance frequency f ₀ of the speaker decreases due to long-term use.

[0007] For this reason, recently, there have been many cases where a meta-type polyamide woven fabric, which is superior in strength to cotton woven fabric and has a small f ₀ change rate, is used as a base material. The loss is low, and the distortion with the phenol resin is poor because it is not well compatible with the phenol resin, so that the reduction in the f ₀ change rate of the speaker cannot be significantly suppressed.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above conventional problems and to provide a diaphragm for a speaker, which has a high reliability by reducing the edge resonance and preventing the decrease in the f ₀ change rate of the speaker. It is a thing.

[0009]

In order to solve the above problems, a speaker diaphragm according to the present invention comprises a base material obtained by coating a woven fabric prepared by mixing para-polyamide fibers with phenol fibers and coating a phenol resin and a polymer resin. The outer peripheral portion of the diaphragm main body is joined to the inner peripheral portion of the edge obtained by heat forming into a predetermined shape.

[0010]

[Advantage] With this configuration, the woven fabric mixed with phenol fibers and the phenol resin coated for maintaining the shape are well compatible with each other, so that the adhesiveness is improved and the internal loss of the woven fabric is increased for more integration. The distortion is reduced, and as a result, it is possible to suppress a decrease in the f ₀ change rate of the speaker.

[0011]

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 half sectional view showing the structure of the speaker diaphragm according to the embodiment.
Para-polyamide fiber and phenolic fiber in weight ratio of 30
% Blended woven fabric with 5% by weight of phenolic resin and 20% by weight of chlorosulphonated polyethylene resin, and then heat-formed into a corrugated shape using a molding die and cut into a predetermined shape. The edge 1 thus formed and the diaphragm main body 2 having the outer peripheral portion adhered to the inner peripheral portion of the edge 1 are configured.

The blend ratio of the above phenolic fibers is 1
When the content is 0% or less, the proportion of the phenolic fiber is small, so that the quality of the mixed spinning base material varies, the adhesion with the phenolic resin is weak, and the effect is small, and the phenolic fiber mixed spinning ratio is 30%. In the above case, the tensile strength of the mixed spinning base material is lowered, and the minimum resonance frequency f ₀ at the time of large amplitude is greatly reduced. Therefore, it is important to use the mixed spinning ratio in the range of 10 to 30%.

FIG. 2 shows a sound pressure frequency characteristic of a speaker having a diameter of 16 cm, which is produced by using the speaker diaphragm of the present invention. In FIG. 2, the dotted line shows the output sound pressure frequency characteristic 3 of the speaker using the speaker diaphragm according to the present invention, and the solid line shows the output sound pressure frequency characteristic 4 of the speaker using the conventional speaker diaphragm. , Especially 500 ~
It can be seen that the edge resonance at 2000 Hz is reduced and the characteristic becomes flatter.

FIG. 3 shows the transition of the change rate of the minimum resonance frequency f ₀ with time of the speaker. As is clear from FIG. 3, the speaker using the speaker diaphragm according to the present invention has a f ₀ change rate of 5 as a speaker using the speaker diaphragm using the edge 7 made of the conventional meta-aromatic polyamide woven fabric. It is understood that the change rate is smaller than the f ₀ change rate of 6.

In addition, the same effect was obtained by using a rubber-based coating agent such as styrene-butadiene rubber or nitrile-butadiene rubber in place of the chlorosulfonated polyethylene used in the above examples as the coating agent. Keep it.

[0017]

Since the speaker diaphragm according to the present invention is configured as described above, not only the edge resonance generated at the edge portion of the speaker diaphragm can be reduced, but also the minimum resonance frequency f ₀ change rate is lowered. It has a great effect of being able to prevent, and has great industrial value.

[Brief description of drawings]

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

FIG. 2 is an output sound pressure frequency characteristic diagram comparing a speaker using the speaker diaphragm according to the example and a conventional speaker.

FIG. 3 is a characteristic diagram showing changes in the minimum resonance frequency f ₀ over time when a speaker using the speaker diaphragm according to the example and a conventional speaker are compared.

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

FIG. 5 is a half cross-sectional view showing the configuration of a conventional speaker diaphragm.

[Explanation of symbols]

1 edge 2 diaphragm main body 3 output sound pressure frequency characteristic of speaker using speaker diaphragm according to the present invention 4 output sound pressure frequency characteristic of speaker using conventional speaker diaphragm 5 Speaker diaphragm according to the present invention f ₀ the rate of change of loudspeaker using the f ₀ change rate 6 conventional loudspeaker diaphragm loudspeaker using

Claims (2)

[Claims] 1. An edge formed by heat-molding a base material obtained by coating a woven fabric obtained by mixing para-polyamide fiber with phenol fiber with a phenol resin and a polymer resin having a high internal loss into a predetermined shape on a peripheral portion of a diaphragm body. A diaphragm for a speaker that is combined. 2. The blending ratio of the phenol fiber mixed with the para-type polyamide fiber is 10 to 30% by weight.
The diaphragm for the speaker described.