JPS5846632Y2 - speaker device - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a speaker device having heat radiation means.

Generally, the electro-acoustic conversion efficiency of an electrodynamic speaker having a voice coil is only a few percent, and most of the electrical energy becomes Joule heat generated from the voice coil.

For this reason, if the speaker was used for a long time with high input power, the temperature of the voice coil would rise considerably, which could cause the adhesive that adheres the voice coil to soften or cause thermal damage to the voice coil. .

Furthermore, since an increase in the temperature of the voice coil is accompanied by an increase in its resistance value, there is a drawback that the linearity of the output sound pressure characteristic with respect to the input voltage is impaired.

On the other hand, most of the heat generated from the voice coil is conducted to the entire field section through both magnetic poles of the magnetic gap formed in the field section, so if the field section is cooled,
This will suppress the rise in temperature of the voice coil.

From this point of view, in order to prevent the above-mentioned accidents and improve the above-mentioned drawbacks, it has been proposed to connect a heat dissipation means to the above-mentioned field part via a heat pipe having high thermal conductivity.

An example of a speaker device having a heat dissipation means as described above is shown in the first example.
As shown in the figure.

In the figure, 1 is an electrodynamic speaker having a voice coil, 2 is a field part of the speaker 1, 3 is a bass reflex type cabinet in which the speaker 1 is installed, and 4 is the cabinet l.
-3 is a cylindrical duct provided on the front surface of the speaker, which amplifies the resonance of the low frequency range of the back sound of the speaker.

Reference numeral 5 denotes a porous metal having a large heat dissipation effect, which is placed inside the cylindrical duct 4 so as to completely cover the duct 4.

Note that this porous metal is made by foaming a metal such as nickel to have a porosity of about 98%.

6 is a heat pipe that connects the porous metal 5 and the field part 2 of the speaker 1, and by repeating evaporation of liquid and condensation of vapor in the sealed pipe, the temperature changes from high temperature to low temperature. It conducts heat to the side.

As mentioned above, the bass reflex type speaker device has a compliance corresponding to the capacity of the cabinet 3 and a duct 1.
The mass of air in the duct 4 creates a spring-mass resonance system, which generates low sound, so the flow of air in the duct 4 is very large.

Furthermore, the porous metal 5 installed in this duct 4 is itself a good heat conductor and has a porosity of about 98%, so its surface area is larger than that of a general heat dissipation fin.
It is very large.

Therefore, the field part 2 of the speaker 1 is
The heat conducted from the duct to the porous metal 5 in the duct 4 is
Heat is efficiently radiated to the air vibrating within this duct 4.

In the speaker device having such a configuration, the overall thermal conductivity of the heat conduction path consisting of the field portion 2, the heat vibro having high thermal conductivity, and the porous metal 5 having a large heat dissipation effect is the highest thermal conductivity. affected by low rates.

Therefore, while the thermal conductivity of each of the above parts, especially the joint between the field part 2 and the heat vibro, is a problem, in order to increase the degree of thermal conductive coupling between the field part 2 and the heat vibro, It is desirable to make the long hole drilled in the magnetic part 3 and the diameter of one end of the heat vibrator inserted into the long hole the same, and to tightly fit and connect the two, but high precision is required in terms of dimensions, and the work is difficult. It also has poor performance and causes an increase in costs.

The present invention has been made in view of this point.

FIG. 2 shows the connecting portion between the field section and the heat pipe of the speaker device of the present invention.

In the figure, 7 is a bottom plate having a center pole 8 in the center, 9 is an annular ferrite magnet placed on the bottom plate 7, and 10 is a top plate placed on the annular ferrite magnet 9. , and forms an equal magnetic gap with the center pole 8.

11 is a coil bobbin around which the voice coil 12 is wound, and is inserted into the magnetic gap.

Reference numeral 13 denotes a frame joined to the above-mentioned top playback (10), and the outer periphery of the open end of this frame 13 is connected to the through hole of the cabinet 3, so that the speaker 1 is mounted on the cabinet 3.

14 is a diaphragm held at the open end of the frame;
It is coupled to the coil bobbin 11 together with the tamper 15.

Reference numeral 16 denotes a long hole bored at the lower end of the pole piece, into which one end of the heat vibro is inserted.

17 is a magnetic fluid filled in the elongated hole, and the diameter is 10
It is made by mixing magnetite powder of about 0A into oil etc. in colloidal form.

This magnetic fluid is, for example, available under the trade name Ferrofluid manufactured by Ferrofludics, Inc. in the United States, and is known to have excellent thermal conductivity.

As mentioned above, the long hole 16 bored in the center pole 8
The magnetic fluid 17 filled in the center pole 8 is attracted by the magnetic flux passing through the center pole 8, so it does not scatter and completely fills the gap between one end of the heat vibro and the elongated hole 16 over a long period of time. It's something you get.

Therefore, the field part 2 and Hee I Vibro are the magnetic fluid 17
They will be thermally coupled due to the

The speaker device of the present invention is a speaker device in which a heat dissipation means is coupled to the field part of the speaker via a heat pipe.
A long hole is drilled in the center pole that constitutes the field part,
Since one end of the heat pipe is inserted into the elongated hole and is filled with magnetic fluid, the heat pipe and the field part can be thermally coupled very easily.

Therefore, the heat generated in the voice coil is efficiently conducted from the center pole of the field part to the heat pipe via the magnetic fluid with high thermal conductivity, and is further transferred to the air by the heat dissipation means connected to the heat pipe. Since the heat is radiated, the rise in temperature of the voice coil is well suppressed, and it is possible to prevent the voice coil from being damaged by heat, and it is possible to maintain the linearity of the output sound pressure characteristic with respect to the input voltage.

Furthermore, the dimensional accuracy of the center pole of the field part and the diameter of the heat pipe does not need to be very high, and problems in terms of workability in connecting the two are completely resolved, and it is extremely cost-effective. It's advantageous.

[Brief explanation of drawings]

Figure 1 is a sectional view showing the concept of the speaker device, Figure 2 is
It is a cross-sectional view of the main parts of the speaker device of the present invention, 6 is a heat pipe, 8 is a pole piece, 12 is a voice coil, 16
1 indicates a long hole, and 17 indicates a magnetic fluid.

Claims (1)

[Scope of utility model registration request] In a speaker device in which a heat dissipation means is coupled to the field part of an electrodynamic speaker having a voice coil via a heat pipe, a long hole is bored in the center pole that constitutes the field part, and Insert one end of the heat pipe and
A speaker device characterized by being filled with magnetic fluid.