JP3039081B2 - 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. 5 is a cross-sectional view showing the structure of a conventional speaker diaphragm, in which a urethane foam or a cotton woven fabric coated with a phenol resin and a polymer resin is formed into a corrugated shape by heating using a molding die. The peripheral portion of the diaphragm 10 is fixed to the inner edge of the edge 9 to form a speaker diaphragm.

FIG. 6 is a half sectional view showing the structure of a conventional diaphragm for a speaker formed similarly to FIG.
An example using an edge 11 formed by heat molding into a roll shape is shown,
The conventional speaker diaphragm is configured as described above.

[0005]

However, in the above-mentioned conventional configuration, when a urethane foam is used for the edge 9 or 11, the internal loss of the material is high, which is advantageous in terms of the sound quality of the speaker. The cost is high due to the long molding time required for molding into a compact, and the field of application is limited due to severe deterioration of physical properties due to ultraviolet rays and humidity. When a cotton woven fabric is used for the edge 9 or 11, the cost is low, the physical property deterioration due to ultraviolet rays and humidity is reduced, and the edge 9 or 11 can be widely used. deformation not only is edge resonance occurs greatly when the lowest resonance frequency f _o of the speaker has a problem that decreases the long-term use of.

[0006] As Therefore recently increasingly those using the rate of change of the lowest resonance frequency f _o excellent in strength than cotton fabric also less meta-aromatic polyamide fibers as the substrate. However, low internal loss of the base material, or distortion due familiar bad of a phenol resin is high, there is a problem that it is impossible to suppress a reduction in the rate of change of the lowest resonance frequency f _o of the speaker greatly .

[0007] The present invention solves the conventional problems described above, advance to prevent the deterioration of reduction and the rate of change of the lowest resonance frequency f _o of the speaker edge resonance, to provide a speaker diaphragm having a high reliability It is intended for.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a speaker diaphragm according to the present invention comprises a cotton fiber woven on the surface of a woven fabric of a meta-aromatic polyamide fiber, and the woven fabric impregnated with the cotton fiber. A thermosetting resin, a high-loss internal polymer resin coated many times, and an edge formed by heat-forming the base material to the outer periphery of the diaphragm main body. is there.

[0009]

As described above, by using a woven fabric in which cotton fibers are woven on the surface of a woven fabric of a meta-aromatic polyamide fiber, the strength of the base material is increased and the lowest resonance frequency f _{o of the} speaker is obtained.
Can be suppressed from decreasing. In addition, by using a heat-crosslinkable resin having a high internal loss for the coating agent, distortion of the speaker can be reduced, and reliability such as heat resistance and moisture resistance can be improved.

[0010]

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 a speaker diaphragm according to the present invention, and FIG. 2 shows an edge substrate used for the diaphragm of the present invention. In FIG. 2, on the surface of a plain woven fabric (basis weight 80 g / m ² ) 3 of a meta-polyamide fiber having a 40-th thickness, a 40-th-thick cotton fiber 4 is obliquely woven into a base material, A phenol resin is impregnated with 5% by weight, and a chlorosulfonated polyethylene resin is coated on one side three times at a weight ratio of 40%, and then heated and molded into a corrugated shape using a molding die, and cut into a predetermined shape. To form an edge 1 shown in FIG.
The diaphragm main body 2 is adhered to the inner peripheral portion of the speaker to constitute a diaphragm for a speaker.

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

Further, showing changes in the rate of change of the lowest resonance frequency f _o at the time course of the speaker in FIG. F _o rate of change of loudspeaker using the speaker diaphragm by obvious the present invention of FIG. 4, the speaker using the speaker diaphragm with edge 9 of the conventional meta-aromatic polyamide fabric small it can be seen compared to the f _o the rate of change.

Similar effects were obtained by using an acrylic heat-crosslinkable resin instead of the chlorosulfonated polyethylene used in the above examples as a coating agent.

[0015]

Since the present invention is configured as described above,
It is also possible to prevent a reduction in can be reduced edge resonant lowest resonance frequency f _o change rate, but a large consisting of industrial value which can be further improved reliability such as heat resistance and moisture resistance.

[Brief description of the drawings]

FIG. 1 is a half sectional view showing a configuration of a speaker diaphragm in one embodiment of the present invention.

FIG. 2 is an explanatory view showing a woven fabric according to the embodiment.

FIG. 3 is an output sound pressure frequency characteristic diagram of a speaker using the speaker diaphragm according to the embodiment and a conventional speaker diaphragm.

Characteristic diagram showing the change of the lowest resonance frequency f _o at the time course of the speaker using the speaker diaphragm according to Figure 4 conventional value Example

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

FIG. 6 is a half sectional view showing a configuration of a conventional speaker diaphragm.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Edge 2 Diaphragm main body 3 Meta-based aromatic polyamide fiber which is an edge base material 4 Cotton fiber which is the same base material

Claims (3)

(57) [Claims] 1. A cotton fiber woven on the surface of a woven fabric of a meta-aromatic polyamide fiber, a thermosetting resin impregnated in the woven fabric, and a high internal loss polymer coated on the woven fabric many times. A diaphragm for a speaker in which a resin and an edge obtained by subjecting the base material to a predetermined shape by heat molding are connected to an outer peripheral portion of the diaphragm main body. 2. The knitting of a woven fabric of a meta-based aromatic polyamide fiber and a cotton fiber is performed by knitting a cotton fiber obliquely on the surface of a plain woven aromatic polyamide fiber woven fabric. Item 2. A speaker diaphragm according to item 1. 3. The diaphragm for a speaker according to claim 1, wherein a thermally crosslinked resin such as a chlorosulfonated polyethylene resin is used as the high internal loss resin.