JP3148686B2 - Manufacturing method of speaker diaphragm - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a diaphragm of a dome type speaker.

[0002]

2. Description of the Related Art Conventionally, a dome-shaped diaphragm 11 as shown in FIG. 3 (A) has been used for a speaker unit for medium and treble sounds. A diaphragm 12, a voice coil bobbin 13 and an edge 14 are provided. After the coil portions 12 are formed on the voice coil bobbin portion 13 and formed separately, these are bonded with an adhesive 15.

[0003] As shown in FIG. 3 (B), a diaphragm portion 1 has been proposed as one that can reduce the weight of the high-frequency sound wave propagation without loss.
There has been proposed a diaphragm base material in which a voice coil bobbin portion 1 and an edge portion 14 are integrally formed. As a result, the influence of the adhesive used conventionally can be eliminated,
Although the weight reduction and the stability were able to be greatly improved, on the other hand, the molding surface of the material was limited, and the material having a high acoustic wave propagation speed generally had low elongation and was impossible to mold.

[0004]

In order to increase the propagation speed of sound waves and extend the frequency characteristics of the loudspeaker to a high-frequency range, we first deposit a vapor-deposited film 16 made of a high-sonic-speed material, such as diamond, on the diaphragm 11. We suggest what we have formed and have achieved certain results.

However, when the coil is formed by winding the coil around the voice coil bobbin 13, since the winding is performed while an organic adhesive is applied to the wire, the propagation speed of the sound wave is increased. The effect of this adhesive cannot be eliminated.

Further, the diaphragm is susceptible to breakage due to ceramicization (mineralization) due to the above-described vapor deposition process. However, since the diaphragm is wound around the voice coil bobbin of the diaphragm in the easily damaged state, the diaphragm is damaged in the winding step. There is a point to be solved such as the occurrence of a defect which causes a defect.

An object of the present invention is to provide a method of manufacturing a speaker diaphragm which can solve the above-mentioned drawbacks of the conventional speaker diaphragm and can easily manufacture a speaker diaphragm further improving the speaker diaphragm proposed by us. It is in.

[0008]

According to a method of manufacturing a speaker diaphragm of the present invention, there is provided a dome-shaped diaphragm comprising a diaphragm, a voice coil bobbin integrally formed therewith, and a coil formed on the voice coil bobbin. In the method of manufacturing a plate , a coil portion is formed by winding around a voice coil bobbin portion, and then the coil portion is set on a rotary radiator in a chamber of a plasma generator in a thermal plasma CVD method, and the coil is formed. covering the outer periphery of the parts in the cooling jig, the plasma generating instrumentation
Place the plasma torch on the top of the dome-shaped diaphragm,
By the discharge from the plasma torch, the thermal plasma C
By vapor deposition by the VD method, an evaporated film of an amorphous diamond film or a crystalline diamond film is formed so as to cover the diaphragm portion and the upper end of the coil portion from the diaphragm portion, and the outer periphery of the coil portion is formed. In the part, the deposited film
It is characterized in that it is not formed .

[0009]

A diaphragm base material in which a diaphragm portion and a voice coil bobbin portion are integrally formed is obtained, and the coil portion is formed by winding around the voice coil bobbin portion. This is set on a rotary radiator in a chamber of a plasma apparatus in a conventionally known thermal plasma CVD method, and the outer periphery of the coil portion is covered with a cooling jig separately manufactured, and a plasma torch of the plasma generator is mounted.
Of the plasma torch
Vapor deposition is performed by thermal plasma CVD by discharge . As a result, the evaporated film of the inorganic material almost covers the diaphragm portion and the upper end portion of the coil portion from the diaphragm portion.
It is formed uniformly, and the surface of the organic adhesive in the coil portion is also covered with the deposited film.

According to this manufacturing method, since the vapor deposition process is performed with the coil portion formed, the diaphragm base material is not damaged in the winding step. In the speaker diaphragm thus obtained, since the upper end of the coil bobbin and the upper end of the coil are covered with a vapor-deposited film made of an inorganic material, as well as the diaphragm, the influence of the adhesive on the coil is reduced. Thus, the sound wave propagation speed can be further increased.

[0011]

FIG. 1 is a schematic sectional view of a speaker diaphragm obtained by a method of manufacturing a speaker diaphragm according to the present invention, and FIG. 2 is a thermal plasma CVD method used in the method of manufacturing a speaker diaphragm. FIG. 2 is a schematic diagram of a plasma generator in FIG.

In FIG. 1, A shows the whole speaker diaphragm, in which a dome-shaped diaphragm portion 1, a voice coil bobbin portion 3 and an edge portion 4 are integrally formed to form a diaphragm base material 10, and a wire material is applied to the voice coil bobbin portion 3. The formation of the coil portion 2 by winding is the same as the conventional one, but the inorganic material is deposited so as to cover the upper surface of the diaphragm portion 1 and the upper end of the coil portion 2 from the diaphragm portion 1. A film 6 is formed.

Next, a specific method for manufacturing the speaker diaphragm A as described above will be described with reference to FIG. As we all know,
A thermal plasma generator in a thermal plasma CVD method (chemical transport method) includes a plasma torch 2 for generating thermal plasma.
1 and the inside of the chamber 22 are evacuated by an evacuation pump 25, and a source gas 23 is supplied. The adherend is set on a radiator 27 through which cooling water 26 circulates, and the radiator 27 rotates.

The plasma torch 21 has an anode (anode) 2
A direct current discharge is caused between the electrode composed of the cathode 1a and the cathode (cathode) 21b. When a raw material gas is supplied, a deposition film of an inorganic material is formed on the adherend.

A 25 micron-thick titanium is press-molded to obtain a diaphragm base material 10 in which a diaphragm portion 1, a voice coil bobbin portion 3 and an edge portion 4 are integrally formed, and a wire is wound around the voice coil bobbin portion 3. By doing so, the coil portion 2 is formed. This is set on the radiator 27, and the outer periphery of the coil portion 2 is covered with a cooling jig 28. The raw material gas to be supplied is, for example, 100: 0.
The ratio is 1: 7, whereby the upper surface of the diaphragm 1 and the diaphragm 1 are formed by a thermal plasma CVD method.
Then, a crystalline diamond film is deposited over the upper end of the coil portion 2 to form a deposited film 6.

According to the present invention, the adhesive portion having the lowest sound speed conventionally has a sound speed of 1700 m / sec.
It can be increased to 8000 meters / second, which is 10 times. In this embodiment, the thermal plasma CV is used as the deposition film 6.
Although the diamond film having the fastest sound speed was formed by the method D, the same effect can be expected as long as the material has performance equivalent thereto, for example, aluminum oxide, silicon carbide, boron, boron carbide, and the like. The same effect can be expected because the inorganic material is 5 to 7 times the sound speed of the adhesive. Further, the vapor deposition film 6 may cover the entire coil unit 2.

[0017]

According to the method for manufacturing a speaker diaphragm according to the present invention, in the obtained speaker diaphragm, the adhesive portion at the upper end of the coil portion having a low sound speed is uniformly covered with a vapor-deposited film made of an inorganic material having a high sound speed. Transmission loss can be reduced, and the deposited film is formed on the outer peripheral portion of the coil portion.
Therefore , the weight increase hardly occurs, and the efficiency decrease and the like can be ignored.

[0018] Such a speaker diaphragm can be easily manufactured. In particular, since the deposition process is performed after the coil portion is formed, the diaphragm may be damaged when the coil portion is formed as in the conventional case. There is no danger.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a speaker diaphragm obtained by a method for manufacturing a speaker diaphragm according to the present invention.

FIG. 2 is a schematic diagram of a plasma generator in a thermal plasma CVD method used in a method of manufacturing a speaker diaphragm.

FIG. 3A is a sectional view of a conventional dome-shaped diaphragm,
FIG. 3B is a cross-sectional view of the dome-shaped diaphragm that we previously proposed.

[Explanation of symbols]

 A Speaker whole diaphragm 1 Vibration plate part 2 Coil part 3 Voice coil bobbin part 4 Edge part 6 Evaporated film 10 Vibration plate base material 21 Plasma torch 22 Chamber 27 Radiator 28 Cooling jig

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H04R 7/02 H04R 7/12 H04R 9/04 105 H04R 31/00

Claims (1)

(57) [Claims] In a method for manufacturing a dome-shaped diaphragm comprising a diaphragm , a voice coil bobbin integrally formed with the diaphragm, and a coil formed on the voice coil bobbin, a voice coil bobbin is provided. after forming the coil portion by winding, which covers the outer periphery of the coil portion at a cooling jig while set onto a rotating radiator in a chamber of a plasma generating apparatus in the thermal plasma CVD method, the plasma onset
Put the plasma torch of the raw device on top of the dome-shaped diaphragm
An amorphous diamond film or a crystalline diamond film is disposed so as to cover the vibrating plate portion and the upper end of the coil portion from the vibrating plate portion by vapor deposition by thermal plasma CVD by discharge from the plasma torch. And an outer peripheral portion of the coil portion is formed.
A method for manufacturing a speaker diaphragm, wherein a vapor-deposited film is not formed .