JPH0364199A - Manufacture of diaphragm for speaker - Google Patents

Abstract

PURPOSE:To obtain a diaphragm for speaker excellent also acoustically with a simple work process by clamping a cloth made edge member to a specific molding die and applying injection molding to a plastics being a material of the diaphragm. CONSTITUTION:A cone type diaphragm cavity 11 is formed to a molding die 1 in a couple of forming dies 1, 2 and an edge cavity 21 is formed along a parting line at a position corresponding to the periphery of the cone type diaphragm cavity 11 to the forming die 2 and a gate 12 is formed to the molding die 1. Then a cloth made edge (e) formed in advance is accommodated in the edge cavity 21 of the molding die 2 and the molding dies 2, 1 are parted. Then a desired plastics is injected as a material for the diaphragm through the gate 21 and the plastics impregnates the cloth of the cloth made edge densely. Thus, the diaphragm for speaker excellent also acoustically with a simple work process.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for manufacturing a diaphragm for a speaker, and more specifically, a diaphragm for a speaker that integrally molds a diaphragm made of plastic and an edge made of cloth. Relating to a manufacturing method.

[Conventional technology]

Most conventionally known diaphragms, especially plastic diaphragms, are manufactured by injection molding.

In this case, if the diaphragm and the edge can be integrally molded, not only a diaphragm alone but also a product that is closer to a finished product can be obtained, making the manufacturing process more efficient.

Therefore, it is common practice to obtain a diaphragm by integrating the diaphragm and the edges with adhesive, or to mold the diaphragm using two-color molding or insert molding. If you use polypropylene, a plastic with excellent characteristics as a diaphragm, it is difficult for adhesives to stick to polypropylene because its surface is inert, so primer treatment or other processes are necessary before applying adhesive. , corona discharge treatment has been applied.

[Problem to be solved by the invention]

In the diaphragm manufacturing method described above, adhesive is present between the diaphragm and the edges, and the adhesive prevents vibrations from propagating on the surface of the diaphragm, causing variations in the vibration propagation speed. In addition, there were problems in that the bonding process was essential and the work process was unavoidably complicated.

Therefore, it is an object of the present invention to provide a speaker diaphragm with excellent acoustics through a simple work process.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention is characterized in that after a cloth edge material is clamped to a mold having an edge cavity, plastic, which is the diaphragm material, is injected into the diaphragm cavity. This method is characterized in that after a cloth edge material is clamped in a mold having a packing cavity continuous with the edge cavity, plastic, which is the diaphragm material, is injected into the diaphragm cavity and the packing cavity.

[For production]

Even if you choose an ideal plastic material for the diaphragm and a cloth material for the edge, there will be no problem in integrating the two, and the simple process will ensure quality. Obtain an excellent speaker diaphragm.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings. First, in these figures, reference numeral 112 indicates a pair of molds, mold 1 has a cone-shaped diaphragm cavity 11 formed therein, and mold 2 has a cone-shaped diaphragm cavity 11 formed therein. An edge cavity 21 is formed along the parting line at the position.

Further, a gate 12 is formed in the mold l,
Plastics suitable for diaphragms can be injected.

In molding the diaphragm, a preformed cloth edge e is housed in the edge cavity 21 of the mold 2, and the mold 2 and the mold l are parted. Thereafter, a desired plastic material is injected from the gate 12 as the diaphragm material. As a result, the plastics densely penetrates into the grains of the cloth edge, thereby producing a speaker diaphragm in which a diaphragm made of plastic, for example, polypropylene resin, and a cloth edge are integrated. The characteristics required for Edge are better than those made of airtight cloth than plastics, so it is easy to obtain a diaphragm with excellent playback characteristics, and an adhesive is not required to integrate the two. There are advantages in terms of work processes as there is no need to

Furthermore, an enlarged view of the integrated part of the diaphragm and the edge e is shown in Figure 2, and the inner peripheral edge el of the edge e is either above the diaphragm - (A in the same figure) or below. Examples include those sandwiched between the diaphragm 1 (FIG. 1C), and those sandwiched between the diaphragm 1 (FIG. 1C).

Further, the edge e is coated with plastic on both sides or on either side.

Further, according to another embodiment of the invention, in the mold 2,
If a packing cavity 22 is formed on the outer periphery of the edge cavity 21 continuously to the edge cavity 21, and a gate 23 leading to this cavity 22 is provided, the packing p will be integrated with the edge and molded. can do.

In this case, the state of bonding between the packing p and the edge e is as shown in FIGS. 4(A), (B), and (C).
Or it can be on the underside, or even in a sandwich format.

〔Effect of the invention〕

As is clear from the above explanation, according to the method of manufacturing a speaker diaphragm of the present invention, the speaker edge and the plastic diaphragm are integrated without using adhesive, and excellent reproduction f characteristics are achieved. A diaphragm can be obtained, and according to the present invention, in addition to the edges, the packing can also be integrally formed.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a mold used in the manufacturing method of this invention;
Fig. 2 is an enlarged sectional view showing a part of a speaker diaphragm obtained by the same method, No. 3 rgJ is a sectional view of a mold used in the method of another invention, and Fig. 4 is a sectional view of a speaker diaphragm obtained by the same method. It is an enlarged sectional view showing a part. 1... Molding die, 2... Molding die, m... Diaphragm, 11... Cavity for diaphragm 21... Cavity for edge

Claims (2)

[Claims] (1) A method for manufacturing a speaker diaphragm, which comprises clamping a cloth edge material to a mold having an edge cavity, and then injecting plastic, which is a diaphragm material, into a diaphragm cavity. (2) After clamping the cloth edge material to a mold having a packing cavity continuous with the edge cavity, the packing is characterized by injecting a diaphragm cavity and a plastic material, which is the diaphragm material, into the packing cavity. A method for manufacturing a speaker diaphragm.