JPH0119315B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a diaphragm for a flat speaker.

Conventional diaphragms for flat-plate speakers are made of SBR (styrene-butadiene rubber), as shown in Figure 1.
A sound emitting part 1a and an edge part 1b are integrally molded from synthetic rubber such as NBR (acrylonitrile-butadiene rubber) to form a diaphragm 1, and a reinforcing plate (aluminum plate ) 3 bonded together, and the diaphragm 1, cardboard 2, and aluminum plate 3 were bonded together using a hot melt adhesive.

The conventional manufacturing method consists of (1) molding synthetic rubber into a predetermined diaphragm shape and roughening the adhesive surface on the back (2) on the other hand, applying hot-melt adhesive to both sides of the cardboard. The process of laminating the sheets and punching them into a predetermined shape (3) On the other hand, the process of punching an aluminum plate into a predetermined shape (4) A diaphragm is set in an adhesive mold, and a cardboard is placed on top of it. Then, after placing an aluminum plate on top of it, heat and pressure is applied to melt the adhesive.
It consists of each process of gluing a diaphragm, a ball plate, and an aluminum plate.

Note that the reason why the cardboard 2 is interposed and bonded between the diaphragm 1 and the aluminum plate 3 is to absorb air bubbles present between the diaphragm 1 and the aluminum plate.

The manufacturing method described above has the disadvantage that the process of molding the diaphragm and the process of adhering the diaphragm, cardboard, and aluminum plate are separate processes, and that cardboard is required to absorb air bubbles.

The present invention improves on these conventional drawbacks, and is characterized in that the diaphragm and reinforcing plate are bonded together at the same time as the diaphragm is molded.

Hereinafter, the present invention will be explained with reference to the drawings from FIG. 2 onwards.

[Example (1)] On the acoustic radiation part molding part 4a of the lower mold 4, a reinforcing plate is coated with a hot-melt adhesive such as NO-220 (trade name) manufactured by Road Far East Inc. and dried. , for example diameter 300
An aluminum plate 3 with a thickness of 0.8 mm and a molding material such as SBR or NBR is placed on it, and the synthetic rubber sheet 5a is placed on the edge molding part 4b of the lower mold 4. A synthetic rubber 5b made of the same material as the sheet 5a is placed. After that, the upper mold 6 is lowered and the synthetic rubber sheet 5a and the synthetic rubber 5b are heated and pressurized at a temperature of 160°C for 2 minutes, so that the synthetic rubber sheet 5a and the synthetic rubber 5b are melted in the mold. The acoustic radiation part and the edge part of the diaphragm are integrally molded so that they are fluid and interconnected, and at the same time, the diaphragm and the aluminum plate 3 are bonded together.

The thickness of the diaphragm was 0.8 mm for both the acoustic radiation part and the edge part.

According to the above manufacturing method, molding of the diaphragm and adhesion of the diaphragm to the aluminum plate are performed in the same process, and since the diaphragm is molded by melting synthetic rubber in the mold, air bubbles are mixed in. There is no risk of it happening.

[Example (2)] In Example (1), a heat-resistant tempered glass plate (length: 300 mm, length: 1 to 3 mm) is used instead of the aluminum plate as the reinforcing plate.

In Example (1), the aluminum plate is heated to about 160°C by the mold during molding and bonding of the diaphragm, so it is thermally deformed and the one with an outer diameter of 300 mm becomes 303
~305mm, whereas in this example,
There is no deformation of the heat-resistant tempered glass plate.

[Example (3)] In Fig. 3, in a mold, an aluminum plate 3 is sandwiched between synthetic rubber sheets 5a and placed on a lower mold 4 to form and bond a diaphragm. It's a method. That is, this is a method of embedding the aluminum plate 3 in a molding material and molding it.

This embodiment is characterized in that there is no need to apply adhesive to the surface of the aluminum plate 3, and there is no adhesion failure.

However, when assembling the speaker, it is difficult to bond the diaphragm 7 and the voice coil bobbin 8, so as shown in Figure 4, the diaphragm material (synthetic rubber) at the bobbin bonding part of the diaphragm 7 is peeled off and aluminum is used. The plate 3 is exposed and the voice coil bobbin 8 is bonded to this part.

As described above, in the present invention, a reinforcing plate is placed on the acoustic radiation part molding part of the lower mold, a molding material is placed on it, and the molding material is placed on the edge molding part of the lower mold. The above molding material is melted and interconnected in the mold by heating and pressurizing, and the acoustic radiation part and the edge part are integrally molded to form a diaphragm, and this diaphragm and the above reinforcing plate are In the mold, the
A diaphragm can be made by melting and interconnecting molding materials that are separate parts and integrally molding the acoustic radiation part and the edge part.This diaphragm and the reinforcing plate can be formed simultaneously with the integral molding of the diaphragm. It has excellent advantages such as being able to be bonded, thereby simplifying the manufacturing process, and eliminating the presence of air bubbles between the bonding surfaces of the diaphragm and reinforcing plate.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a conventional method for manufacturing a diaphragm for a flat speaker, FIG. 2 is a diagram showing a method for manufacturing a diaphragm for a flat speaker according to the present invention, and FIGS. 3 and 4 are the same and others. It is a figure showing an example of. 3 is a reinforcing plate, 4 is a lower mold, 4a is a sound radiation part molding part, 4b is an edge molding part, and 5a and 5b are molding materials.

Claims (1)

[Claims] 1 Place the reinforcing plate 3 on the acoustic radiation part molding part 4a of the lower mold 4, and place the molding material 5a on it, and also put the molding material 5b on the edge molding part 4b of the lower mold 4. By placing and heating and pressurizing,
Melting the molding materials 5a and 5b in the mold,
A method for manufacturing a diaphragm for a flat speaker, characterized in that a diaphragm is formed by integrally molding an acoustic radiation part and an edge part by interconnecting each other, and the diaphragm and the reinforcing plate 3 are bonded together.