JPS62257298A - Diaphragm for speaker - Google Patents

Abstract

PURPOSE:To flaten the sound pressure level in high audio frequency band by eliminating the variations of tensile strength and bending strength and the directional modulus of elasticity, thereby preventing a division oscillation from being occurred. CONSTITUTION:The diaphragm for the speaker 1 is constituted of a boron fiber 2 disposed radially along the cone-shape of the plate and the cloth 3 of carbon fiber 3 impregnated with a resin which is to be the base material. For the boron fiber, one having physical characteristics of tensile strength; 300-400kg/mm<2>, modulus of elasticity; 30000-45000kg/mm<2>, and specific gravity; 2.45-2.60, is used. Of the diaphragm for the speaker thus constituted, the direc tional irregularity of the carbon fiber cloth 3 is made much less in comparison with a diaphragm to which the boron fiber 2 merely is laminated with the carbon fiber cloth 3 to composite it. Therefore, the tensile strength and the bending strength do not vary, or the modulus of elasticity is not irregular in directions. As a result, an asymmetrical division oscillation and the lowering of sound pressure level in higher frequency band are prevented from being occurred.

Description

[Detailed description of the invention] [Industrial application field]

This invention can be used for loudspeakers! Regarding the 7J board,
More specifically, the present invention relates to a speaker diaphragm using boron fiber.

[Conventional technology]

A diaphragm for a speaker is required to have characteristics such as being lightweight, having a large Young's modulus, and having a moderately large 81S loss. , metals, etc. Since these substrates have their own drawbacks, they are often used in mixtures or composites with other materials. For example, in the case of a paper motion plate, glass fiber or] lagen was mixed into the bulb to make the paper, and white clay was used to improve heat and moisture resistance, or carbon fiber was mixed to improve the A7 rate and heat resistance. There is something. :;: Prefecture that strengthens the senses! Composite paddy transport plates are also known (−
There is. For example, diaphragms made of glass fibers, Kevlar fibers (aromatic polyamide mm), carbon IQH fabrics, and reinforced with lt4 resin have been developed.

Problem to be Solved by the Invention 1 However, the S moving plate made of these fabrics has four points in the perpendicular direction where the threads intersect with respect to the tentative axis, and four directions in between. There are four sets of symmetry planes in total, but they are symmetrical in other directions, and the four sets of symmetry planes are also symmetrical in the normal μm direction and in the intermediate direction, such as tensile strength, bending strength, etc. The strength and modulus of elasticity required for diaphragms are also significantly different. For this reason, efforts have been made to bond two layers at an angle of 45 degrees with respect to the weaving direction, or to attach three layers at an angle of 30' to eliminate the difference in strength as much as possible. However, when 2 and 3 layers are pasted together in this way, the directionality is not aligned at 360° with respect to the axis of the 01 plate, and there is a large number of overlaps, and the 6J, S, medium weight is medium. This results in an additional disadvantage of increasing costs by 8. Therefore, this invention solves the above-mentioned deficiencies in the conventional ones.
This was done to eliminate the problem, so there is no variation in tensile strength and bending strength, and the elastic modulus also has no directionality.
:Supports the speaker diaphragm to prevent split perturbation and reduce the Pi fE level in the high frequency range to II;? (Means for solving the problem 1) In order to achieve the object, the present invention provides a speaker diaphragm containing boron fibers. Boron fiber is 30
The elastic modulus of 000 kg/ll1m2 or more is 15 radially arranged, and t, t + A and 1 = body (L) are constructed so that they are 1 [u, 1]. Embodiment] Hereinafter, an embodiment of the present invention will be explained with reference to the drawings.1゜Figures 1 and 2 show a cone-shaped speaker diaphragm according to the present invention (T' surface 4). Oh, Nibi IJFi
Surface 14 total 14° In Figures 1 and 2, 1 is] -
This is a diaphragm for a speaker in the shape of a ring, and is composed of a rag 2 which is arranged radially along the shape of the ring, and a fabric 3 made of charcoal-M fiber impregnated with resin. . This carbon I! Textile 3 of the work will be used as beam material. This boron OX <<t is tensile strength 1g 300-400
kg,,' m+n2, elastic modulus 30000-4500
0klJ/mT12. Those having physical properties with a specific gravity of 2.45 to 2.60 are used. Next, a method for cracking the speaker diaphragm 1 having the above-described structure will be explained with reference to FIGS. 314 and 4. First, as shown in FIG.
Heating and pressure molding are carried out. Next, as shown in FIG. 4, boron fibers 2 are arranged radially along the cone shape on top of the fabric 3 molded with a mold, and carbon fibers impregnated with resin are placed on top of the grooves. The woven fabric 3 is arranged and heated and pressure-molded using a mold 4 to form one spiral slope 1 for a speaker. The speaker diaphragm 1 configured in this way is made of carbon II
The directionality of the carbon fiber fabric can be improved due to the influence of the highly elastic boron collar fibers compared to a composite obtained by superimposing boron fibers on the M fabric. 1 In the above example, 4: L I +, charcoal impregnated with resin as l! ! Although the description has been made using the fabric of the lapel, other materials that can be used as the base material include paper, resin, foamed plastic, gold rA, and the like. Effects of the Invention As described above, according to the present invention, boron fibers are arranged radially in all directions of 360° with respect to I in the center of the diaphragm.
．． (By integrating into the material, the tensile strength is 1!'t
Since there is no variation in bending strength and the elasticity -I- has the right direction, it is possible to prevent asymmetrical v1 vibration from occurring and a decrease in the field pressure level in the high frequency range.

[Brief explanation of drawings]

FIG. 1 is a plan view and a sectional view of a speaker diaphragm according to an embodiment of the present invention, FIG. 2 is a partially enlarged sectional view of FIG. 1, and FIGS. 3 and 4 are speaker diaphragms according to the present invention. It is a figure for explaining the manufacturing method of a board. 1...Speaker diaphragm, 2...Bottom 1-1, 3...Gi 4i (fabric), 4...1L Patent I"11 Depositor Pioneer Co., Ltd. Agent
Patent Attorney Kobashi 13 Ukiyo Patent Attorney
1) 1 Figure 1 Figure 2 Figure 35! J Figure 4

Claims (1)

[Claims] In the speaker diaphragm containing boron fibers, the boron fibers have an elastic modulus of 30,000 kg/mm^2 or more, are arranged radially, and are formed integrally with the base material. Features speaker diaphragm.