JPS6044880B2 - Manufacturing method of voice coil for speaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a voice coil for a speaker that does not cause deformation of the coil bobbin, does not cause skin damage to workers, and has an improved heat resistance temperature of 200 to 240°C.

Conventional voice coils for speakers have been manufactured by winding a magnet wire having an alcohol-reactivated fusion layer around the outer periphery of a coil bobbin coated with alcohol-reactivated polyamide resin while applying alcohol.

When a speaker was assembled using a voice coil obtained by this method and an input resistance test was performed, it was found that when the temperature of the coil reached 120 to 160°C, the bond between the magnet wires or between the magnet wire and the coil bobbin was broken. This caused the coils to come loose or come off, resulting in accidents such as abnormal noise and wire breakage.

In order to improve the heat resistance of such voice coils, a method has also been developed in which a thermosetting resin such as epoxy resin or phenol resin is applied onto the coil and heat-treated at a temperature of 160 to 200° C. for about 30 minutes.

However, this method has a limited pot life, the heating temperature is as high as 160 to 200°C, which causes deformation of the coil bobbin, and there are environmental health problems such as skin damage to workers. There were many problems such as. The present invention eliminates the drawbacks of the prior art as described above. Embodiments of the present invention will be described below with reference to FIGS. 1 and 2 of the drawings.

A resin film such as kraft paper aromatic polyamide or aluminum foil is used as the coil bobbin 1, and an alcohol reactivated polyamide resin film 2 is applied to the surface of the coil bobbin 1.
A magnet wire 5 having an alcohol-reactivated polyamide resin film as the fusing layer 3 and a polyurethane resin film as the insulating layer 4 is wound thereon to form a voice coil while applying methanol with a brush. Soluble acrylic-polyamide copolymer resin liquid 6
was applied with a brush, air-dried for 3 coats, and then heated and dried for 3 coats at 150°C to obtain a voice coil.

The resin solution 6 of the alcohol-soluble acrylic-polyamide copolymer used has the composition shown in Table 1 below.

As shown in Table 2 above, the temperature of the voice coil before failure was 140°C in the conventional product, and 220°C in the product of the present invention.
It was found that it had nearly twice the power resistance and was sufficiently effective.

In addition to the examples shown in the above examples, winding was performed while applying resin solution 6 of an alcohol-soluble acrylic-polyamide copolymer having the composition shown in Table 1 instead of methanol, and after air drying 3 times, Even after heating and drying for 30 minutes with (substitute), the input resistance characteristics were almost the same as those shown in Table 2.

As described above, according to the method for manufacturing a speaker voice coil of the present invention, a resin solution of an alcohol-soluble acrylic-polyamide copolymer is applied to the fusion layer of the coil bobbin and the magnet wire, air-dried, and 15C)C. Since the coil bobbin is simply heated and dried, there is no deformation of the coil bobbin, and since it is made of the above-mentioned copolymer resin, the heat-resistant temperature can be reduced to approximately 5.
0%, the power resistance can be approximately doubled, and its industrial value is great.

[Brief explanation of drawings]

FIG. 1 is a half-sectional front view of a speaker voice coil manufactured by an embodiment of the speaker voice coil manufacturing method of the present invention, and FIG. 2 is an enlarged sectional view of the same manufacturing process. 1●...◆●Coil bobbin, 2II11 alcohol reactivated polyamide resin film, 3... fusion layer, 4...
...Insulating layer, 5... Magnet wire 1, 6.
...Resin solution of alcohol-soluble acrylic-polyamide co-monomer.

Claims (1)

[Claims] 1 When winding a magnet wire having an insulating layer and an alcohol-reactivated fusion layer on the surface on a coil bobbin having an alcohol-reactivated polyamide resin film on its surface, or after winding is completed, an alcohol-soluble acrylic-polyamide copolymer is used. A method of manufacturing a voice coil for a speaker, which is characterized by applying a resin solution, drying naturally, and then curing by heating.