JPS5843344Y2 - Diaphragm for speakers - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the structure of a diaphragm for a speaker.

Generally speaking, diaphragms for speakers are made of a material that is lightweight and has a low specific gravity, and is made thicker to give it more rigidity.

Various methods have been considered to create pores in the diaphragm.

The diaphragm obtained by press-molding metal particles into the shape of a diaphragm and bonding by firing has a small bubble rate, is heavy, and has the drawback of poor efficiency when used in a speaker.

Since the foamed metal used to form the diaphragm shape has open cells, it is necessary to provide a skin layer on the surface of the diaphragm to prevent air leakage, and the manufacturing process for providing the skin layer is complicated. Because of this, it was heavy, and when used in speakers, it also had the disadvantage of poor efficiency.

A diaphragm made by mixing a ceramic hollow body and a synthetic resin, forming it into a diaphragm shape, and bonding the ceramic hollow body with the synthetic resin is lightweight, but because it is bonded through the synthetic resin, the Young's modulus is small. There were drawbacks.

The present invention was devised to eliminate the above-mentioned drawbacks, and to explain the embodiment shown in the drawings, as shown in FIG. As, 20 parts of aluminum hollow body, 5i0240-49 parts as ceramic binder 3, A
12037.7 parts ~ CaO3-8 parts, K2O4, 5 parts,
2015 parts of Na, 0.5 to 107 parts of Ni, 10 parts of nitrocellulose, 50 parts or more of alcohol ((-n'1-
(weight ratio) is mixed and applied to the substrate 1.

Next, it was placed in an oven, heated from room temperature to 150°C, and dried for 20 minutes, then placed on a carbon convex mold of the same shape as the diaphragm, and
Raise the temperature to 2500C for 0 minutes, then leave it at 250℃ for 10 minutes.
Hold for 30 minutes to burn out the substrate 1.
The temperature is maintained at 50 DEG C. for about 10 minutes, during which time the phenol-impregnated cloth substrate 1 is incinerated.

Next, the temperature was raised to 700°C and held for 30 minutes, during which time the ceramic binder was melted.

Thereafter, by natural cooling, the ceramic binder solidifies to form a sintered body while keeping the shape of the diaphragm while binding the inorganic hollow bodies to each other.

After the above firing process, the sintered body is produced by mechanically removing the ashed substrate, and as shown in FIG. It becomes a board.

The phenol resin-impregnated cloth used as the base material before firing the diaphragm has the following properties: Compared to other materials, it can be easily molded into a precise diaphragm shape, is inexpensive, and more importantly, it is free from alcohol. It has a strong affinity with the ceramic binder mixed with it, the binder coating layer is strong and stable, and it has the characteristics of reducing accidents such as breakage during the firing process, and as a substrate of the present invention. It is the most suitable material.

Since the diaphragm of the present invention has the above-mentioned structure, it is lightweight and rigid, and since the hollow body 2 is bonded with the ceramic binder 3, the Young's modulus is constant, and it is nonflammable.

A speaker using the diaphragm of the present invention can raise the limit frequency of the treble range and widen the reproduction frequency band in terms of frequency and sound pressure characteristics, and can obtain good reproduction frequency characteristics and can sufficiently withstand high output.

As described above, the present invention is a lightweight speaker diaphragm made by forming a mixed layer of an inorganic hollow body 2 and a ceramic binder 3 on the top surface of a phenol-impregnated cloth substrate 1 that can be formed into the shape of a diaphragm, and then firing it. In addition, the non-flammable speaker diaphragm has a high rigidity and a high Young's modulus, and when used in a speaker, it expands the reproduction frequency band, provides good reproduction frequency characteristics, and can withstand large inputs. This is an idea that provides the following.

[Brief explanation of the drawing]

FIG. 1 is a partial configuration diagram of the diaphragm of the present invention before firing, and FIG. 2 is a partial configuration diagram of the diaphragm of the present invention. 1 is a substrate, 2 is an inorganic hollow body, 3 is a ceramic binder before firing, and 4 is a ceramic binder after firing.

Claims (1)

[Scope of utility model registration request] A diaphragm for a nonflammable speaker is obtained by forming a mixed layer of an inorganic hollow body 2 such as a glass hollow body or a ceramic hollow body and a ceramic binder 3 on the upper surface of a phenol-impregnated cloth substrate 1, and firing the layer.