JPS60186197A - Diaphragm for electroacoustic transducer and its nanufacture - Google Patents

Abstract

PURPOSE:To obtain the diaphragm made of titanium boride by forming a vapor- deposited layer of titanium boride on a base and then separating the vapor-deposited layer and base from each other. CONSTITUTION:The diaphragm base 1 is arranged on a base holder 2a in a vacuum container 2, which is evacuated by a vacuum pump to about 10<-2>- 20<-4>Torr. The base 1 is heated by a heater 2b to 300-400 deg.C and gaseous halide of titanium and boron, hydrogen, and argon gas are admitted into the container 2. The total gas pressure in the conatiner 2 is held at about 2Torr and high frequency electric power is impressed between the holder 2a and a plate 2c to cause glow discharge over the base 1, forming the silicon nitride vapor-deposited layer on the base 1. Then the vapor-deposited layer and base 1 are separated from each other to obtain the diaphragm made of titanium boride.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a diaphragm for an electroacoustic transducer and a method of manufacturing the same.

Generally, in order to obtain high-fidelity reproduced sound in a speaker, it is required that the diaphragm do not perform divided vibrations and maintain piston vibration over a fairly wide frequency band.

The frequency at which this split vibration begins to occur is the specific elastic modulus (E/
ρ), selecting a material with a large specific elastic modulus is a factor in improving the reproduction fidelity of the speaker.

However, the specific elastic modulus of natural fibers, synthetic resin fibers, synthetic resin films, metal foils, etc. that have conventionally been used as diaphragm materials is insufficient.

Therefore, in recent years, a ceramic material layer has been layered on the metal foil surface,
Various attempts have been made to increase the specific elastic modulus by nitriding or carbonizing the surface and layering a crystal elastic layer on the surface.

However, the overall specific elastic modulus of the diaphragm that has been surface-treated in this way is extremely lower than that of the high elastic modulus layer on the surface.

In addition, there are problems with the adhesion between the metal foil and the surface layer, and the methods used to form the surface layer, such as vacuum evaporation, sputtering,
Physical vapor deposition methods such as ion deposition and melt EJ = 1
In the method, the growth rate of the surface layer, the thickness of the layer, and the thickness of the layer are determined. It could not be said that the uniformity of q, etc., had been sufficiently resolved.

The present invention relates to a diaphragm for an electroacoustic transducer made of titanium boride having extremely high specific elasticity, and a method for manufacturing the same, and examples thereof will be described in detail below.

As shown in Example No. J1, (1) A diaphragm substrate 1 made of an etched material such as 411 and formed into a diaphragm shape such as a diaphragm shape is placed in a substrate holder 2a in a vacuum container 2. The inside of the vacuum container 2 is evacuated to about 1°4 to 1 OTOrr using a vacuum pump.

(2) Heat the Mf wood 1 & heater 2b to 300-400°C and maintain that temperature.

(3) On the other hand, titanium chloride scum (1.26m).

Argon (purity 9.9, 999%) was used as a carrier gas, and boron trichloride gas (4,05 mo I/br) was used as a reaction gas.
9', 999%) as gear rear gas, and hydrogen gas (/1.26m).

1/hr) into the two vacuum vessels.

(4) Set the total gas pressure in the container 2 to about 2 Tor+, and apply high frequency power (1 Tor+) between the base boulder 2a and the plate 2c.
A titanium boride diaphragm with a thickness of 0.29 mm was formed on the substrate 1 by applying a voltage of 3.56 MH2.6° OW to generate claw discharge on the substrate 1 and reacting for about 10 hours. did.

(5) The substrate on which the vapor-deposited layer was taken out from the container 2 was immersed in a ferric chloride solution, and the top 1 and body 1 were removed to obtain a titanium nitride diaphragm.

The density and Young's modulus of the diaphragm obtained in the above example were measured, and the titanium J, h/cm, specific modulus of elasticity: As is clear from the table, the diaphragm of the present invention was able to increase the specific elastic modulus by about 5 times h compared to the conventional diaphragm.

Furthermore, the manufacturing method of the present invention can form a dense vapor deposition layer without pinballs compared to the conventional physical vapor deposition method, and has good coverage, so a uniform layer can be formed even on a substrate with a complex shape. Not only can you obtain a final layer of good quality, but also!
It is easy to adjust the relative properties using a tweezers, and the layer formation speed is extremely fast (several tens to hundreds of times) compared to physical vapor deposition.
In addition, vapor deposition is possible even when the temperature of the substrate 1 is relatively low, making it extremely suitable for large-scale production.

Furthermore, since the diaphragm according to the present invention has an extremely high specific elastic modulus as mentioned above, it increases the divided vibration generation frequency and thereby expands the piston vibration area.As a result, the high frequency reproduction limit frequency of the speaker is increased and fidelity is improved. It can be pressed.

As explained in Section L below, in this invention, a diaphragm for an electroacoustic transducer made of titanium oxide and a U diaphragm-shaped base are placed in a vacuum container, and the base is heated at 200°C to 4 (
After maintaining the temperature at 10°C, titanium and boron halide gases, hydrogen and argon gas were introduced into the vacuum vessel, and the total gas pressure was 10 to 2 Torr.
'r, generate an alternating current claw discharge, form a vapor deposited N of titanium boride on the substrate (above), and then separate the vapor deposited layer and the substrate to obtain a diaphragm made of titanium boride. This method of manufacturing a diaphragm for an electroacoustic transducer has the advantage of easily providing a diaphragm made of titanium boride of extremely high quality. A speaker using a diaphragm that uses a diaphragm increases its high-frequency reproduction limit frequency and improves fidelity.
1.

[Brief explanation of the drawing] FIG. 1 is a schematic diagram of two manufacturing stages of the diaphragm of the present invention. Patent applicant: Onkyo Corporation

Claims (1)

[Claims] 1. A diaphragm for an electroacoustic transducer made of titanium boride. 2. After placing a diaphragm-shaped substrate in a vacuum container and maintaining the substrate at a temperature of 200°C to 400°C, the respective halide gases of titanium and phosphorus, hydrogen and a,
Rougon gas is introduced into the vacuum container, and the total gas pressure is 1
After adjusting the pressure to 0 to 2 Torr, alternating current glow discharge is generated to form a vapor deposited layer of titanium boride on the base, and then the vapor deposited layer and the base are separated to obtain a diaphragm made of titanium boride. A method for manufacturing a diaphragm for an electroacoustic transducer.