JPH0127356Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a speaker using a diaphragm having a printed voice coil, and particularly aims to improve heat dissipation by improving the diaphragm.

Conventionally, various speakers using a vibrating membrane having a printed voice coil have been developed. This has excellent input response, and because it is a vibrating mass, it has excellent high frequency reproduction and can reproduce up to 150KHz.

As shown in Figures 1 and 2, the diaphragm used in this type of speaker is a printed voice made of aluminum formed in a rectangular spiral shape on the bottom surface of a film 1 of 4μ to 25μ thick made of polyimide resin, etc. It was constructed by pasting a coil 2 with an adhesive 3.

With this configuration, when a current is applied to the printed voice coil 2 with a thickness of several microns to several tens of microns, it is easy to generate heat because the cross-sectional area is very small, and the heat generated in the printed voice coil 2 is dissipated. It had drawbacks such as poor performance and poor input resistance.

This poor heat dissipation means that the rate of increase in the resistance value of the printed voice coil 2 is high, and therefore the linearity of the output sound pressure level with respect to the input is also poor, and the disadvantage is that a large dynamic range cannot be achieved. It was hot.

In order to eliminate these drawbacks, a vibrating membrane as shown in FIG. 3 has been developed.

That is, a printed voice coil 6 made of aluminum is bonded to the lower surface of a film 4 made of polyimide resin or the like using an adhesive 5, and a thin copper foil 8 is attached to the upper surface of the film 4 using an adhesive 7.

However, since the copper foil 8 has a high specific gravity, there is a large increase in mass, resulting in a low output sound pressure level and poor high-frequency characteristics.

Furthermore, since extremely thin copper foil was pasted, it was disadvantageous in terms of cost, making it impractical.

It has also been considered to attach aluminum foil instead of the copper foil 8, but this is not practical due to the manufacturing process as the aluminum foil would melt when etching the printed voice coil 6. It had become a thing.

The present invention eliminates the above-mentioned drawbacks of the prior art.

Embodiments of the present invention will be described below with reference to FIGS. 4 to 7.

9 is a plate-shaped center pole, and on both sides of this center pole 9 are plate-shaped magnets 1.
0,11 are arranged, and these magnets 10,11
Yokes 12, 12 are arranged on the outer surfaces of the magnets 10, 11, and the center pole 9 protruding upward from the upper ends of the magnets 10, 11 and the yokes 12, 13 form magnetic gaps 14, 15 to form a magnetic circuit. are doing. At the upper ends of the yokes 12 and 13, a vibrating membrane 18 made of a film 17 with a printed voice coil 16 on the lower surface is arranged via a fixing ring 19, and this fixing ring 19 is attached to the mounting bracket 20.
is pressed and fixed onto the yokes 12 and 13 by the yokes 12 and 13.

The vibrating membrane 18 has a thickness of 500 Å on the upper surface of a film 17 made of polyimide resin, etc., which has a printed coil 16 made of aluminum on the lower surface as described above.
An aluminum layer 21 with a thickness of ~1000 Å is provided, and a 2-3 μm layer of epoxy resin or the like that acts as an etching resist is provided on the surface of the aluminum layer 21.
A resin layer 22 having a thickness of .

The manufacturing of this vibrating membrane 18 is as shown in FIGS. 5 and 6.
As shown in the figure, an aluminum foil 23 is pasted on the bottom surface of the film 17, and an aluminum layer 21 by vapor deposition and a resin layer 22 by coating are provided on the top surface, and an etching resist is printed in a pattern on the aluminum foil 23 for etching. It is obtained by processing to form the printed voice coil 16.

With this configuration, even if an input signal is applied to the printed voice coil 16 and Joule heat is generated in the printed voice coil 16 as shown in FIG. is transmitted to the aluminum layer 21, and from the end of this aluminum layer 21 to the yokes 12,1.
3 is transmitted to the mounting bracket 20 and efficiently dissipated.

Therefore, the temperature rise can be suppressed and the power resistance can be improved.

As the speaker of the present invention is constructed as described above, the metal layer for heat dissipation is made of extremely thin aluminum, which is advantageous in terms of cost and mass, increases the output sound pressure level, and improves high-frequency characteristics. In addition, since a resin layer is provided on the top of the aluminum layer, printed voice coils can be manufactured by etching, making it possible to fabricate a printed voice coil and making it highly suitable for mass production. The input becomes larger and the dynamic range also becomes larger, which is of great practical value.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a diaphragm used in a conventional speaker, Figure 2 is an enlarged cross-sectional view of the same essential parts, and Figure 3 is a cross-sectional view of the diaphragm used in conventional speakers.
The figure is an enlarged cross-sectional view of the main parts of another conventional vibrating membrane.
Fig. 4 is a sectional view showing an embodiment of the speaker of the present invention, Figs. 5 and 6 are sectional views of main parts showing the manufacturing process of the diaphragm used in the speaker, and Fig. 7 is the heat dissipation system of the speaker. FIG. 9... Center pole, 10, 11... Magnet, 13, 13... Yoke, 14, 15... Magnetic gap, 16... Printed voice coil, 1
7...Film, 18...Vibration membrane, 19...Fixing ring, 20...Mounting metal fittings, 21...Aluminum foil, 22...Resin layer.

Claims (1)

[Scope of utility model registration request] A vibrating membrane made of a film on which a printed voice coil made of aluminum is formed in a portion corresponding to the magnetic gap of the magnetic circuit is coupled to the magnetic circuit, and as the vibrating membrane, a thin aluminum layer is placed on one side of the film on which the printed voice coil is not formed. and a resin layer that acts as an etching resist is formed on the aluminum layer.