JPS6252999B2 - - Google Patents

Description

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

For the edges of the speaker diaphragm, materials with high internal loss are desirable, especially in order to prevent resonance. Materials with a large internal loss include, for example, plastic or plastic foam, and when plastic foam is used to form the edge, it is shaped as shown in FIG. That is, an annular edge component C having the desired edge inner and outer diameters is obtained by cutting from a polyurethane foam fabric material A as a plastic foam, leaving portions B ₁ and B ₂ , and then The edge was formed by heating and pressurizing the edge component C. However, according to this method, it is possible to obtain an edge component C for forming edges only about 1/5 of the total area of the dough material A, and the parts B ₁ and B ₂ are wasted. I was getting used to it.

The present invention has been made in view of the above-mentioned points, and its purpose is to maximize the yield from fabric materials and to produce a large number of edge constituent pieces from one edge constituent base material without wasting it. An object of the present invention is to provide a method for manufacturing an edge for a speaker diaphragm that can be formed.

Hereinafter, the present invention will be explained with reference to FIGS. 2 to 4 together with the apparatus used.

In FIG. 4, 1 is the upper mold, 2 is the lower mold,
The upper mold 1 and the lower mold 2 have the desired shape of the edge to be molded. Then, using the above device,
To form the edge, first, in the first step, a dough material 3 is formed, and in the second step, a cylindrical edge-constituting base material 4 is punched and formed from this dough material 3 (see Figs. 2 and 4). reference). Then, in a third step, the edge forming base material 4 is cut to a predetermined thickness in a direction perpendicular to the axial direction, thereby forming a ring-shaped edge forming piece 4a (see FIG. 3). Furthermore, as a fourth step, the edge component piece 4a is housed in the lower mold 2, and then the upper mold 1 and the lower mold 2 are
Then, the edges are formed by heat treatment and pressure treatment (see FIG. 4).

This will be explained in detail below. First, the formation of the dough material 3 as the first step is performed as follows. That is, in a cylindrical or prismatic container, 100 parts of polyester for urethane, 100 parts of organic diisocyanate, 3.5 parts of blowing agent (water), 0.35 parts of catalyst, and 1.0 part of foam stabilizer (Si) are mixed and stirred by weight. , the slab is foamed and then left to mature for a predetermined period of time. In this case, a soft foam with a foaming rate of 33 times and a specific gravity of 0.025 (±0.02%) was obtained. Note that the foaming rate can be controlled by adjusting the amount of foaming agent. When a hard foam is obtained, the above-mentioned components except the organic diisocyanate are mixed and stirred, the organic diisocyanate is added to the resulting mixture, the mixture is further mixed and stirred, and then aged. In the manner described above, a prismatic material 3 whose upper surface is parallel to the lower surface is obtained. Note that the shape of the dough material 3 may be cylindrical or other shapes.

Next, as a second step, a cylindrical edge forming base material 4 is punched out from the dough material 3 (second step).
figure). 3a and 3b are the remaining parts after punching out the edge forming base material 4 from the dough material 3;
Since b is stamped into a cylindrical shape, it can be effectively used as an edge forming base material with a smaller diameter.

Next, as a third step, by cutting the edge forming base material 3b in a direction perpendicular to the axial direction,
Form a ring-shaped edge component piece 4a (third
figure). After that, the edge component piece 4a is housed in the lower mold 2, and then heat-treated and pressurized using the upper mold 1 and the lower mold 2, so that the edge can be formed (the fourth
figure). The heating temperature in this case varies depending on the composition of the edge component 4a used and the constituent materials of the upper mold 1 and lower mold 2 used, but for example, the heating temperature is 190°C.
℃, and the pressure and pressurization time are approximately 3Kg/
cm ³ ; About 3 seconds.

As described above, the edge component piece 4a obtained by cutting the cylindrical edge component base material 4 punched and molded from the dough material 3 into rings can be easily heat-treated and pressure-treated using the upper die 1 and the lower die 2. Edges can be formed. Further, the edge forming base material 4 can be easily obtained by simply punching and forming the dough material 3, and the remaining parts 3a and 3b after punching the edge forming base material 4
Of these, the cylindrical portion 3b can be effectively utilized by successively punching and forming smaller diameter edge forming base materials 4'.

In addition, it is easy to handle by simply cutting the cylindrical edge-forming base material 4 in the direction perpendicular to the axial direction.
A large number of edge constituent pieces 4a can be formed, and by adjusting the thickness when cutting the edge constituent pieces 4a, edges with different densities or stiffnesses can be easily produced.

Furthermore, when molding the edge component 4a, the upper mold 1, and the lower mold 2, if a diaphragm (not shown) is molded together, the diaphragm and the edge can be easily molded. The installation work can be omitted.

Further, since the foaming rate of the fabric material 3 can be controlled, the density can be adjusted by other than the thickness adjustment during cutting, and an edge with desired acoustic characteristics can be easily obtained from this.

Furthermore, since the dough material 3 can be obtained by mixing predetermined amounts of the raw materials for the dough material 3, there is no need to transport the edge in a foamed state when transporting it to the destination.

As described above, according to the present invention, an extremely useful edge manufacturing method can be provided.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of cutting out an edge component piece from a dough material in a conventional edge manufacturing method, and FIGS. 2 to 4 show each step of the method of an embodiment of the present invention. 3 is a perspective view showing the second step of cutting the edge forming base material from the fabric material, FIG. 3 is a perspective view showing the third step of cutting the edge forming base material to form edge forming pieces, and FIG. FIG. 7 is a cross-sectional view showing a fourth step of forming an edge by forming a constituent piece using an upper mold and a lower mold. DESCRIPTION OF SYMBOLS 1... Upper mold, 2... Lower mold, 3... Dough material, 4... Edge constituent base material, 3a, 3b... Part, 4a... Edge constituent piece.

Claims (1)

[Claims] 1 Polyester for urethane, organic diisocyanate, foaming material, catalyst, and foam stabilizer are mixed and stirred in a cylindrical mold to form a columnar fabric material, and a cylindrical edge-constituting base material is formed from the columnar fabric material by punching. A method for manufacturing an edge for a speaker diaphragm, which comprises: cutting the edge forming base material into rings to form ring-shaped edge forming pieces, and applying heat and pressure treatment to the edge forming pieces using a mold to form edges.