JPS60247400A - Diaphragm for speaker - Google Patents

Abstract

PURPOSE:To obtain a diaphragm which raises the rigidity and the Young's modulus of a diaphragm having a wide frequency band width and reproduces faithfully original sounds, by melt-spraying non-oxide ceramics to the surface of the diaphragm formed with a paper base material as a single substance or melt- spraying a metal or a metal oxide there as a matrix. CONSTITUTION:With respect to materials to be melt-sprayed, a metal nitride such as a boron nitride BN, an aluminium nitride AlN, a silicon nitride Si3N4, a titanium nitride TiN, or the like, a metal boride such as a titanium boride TiB2, an aluminium boride AlB2, or the like, a metal carbide such as a titanium carbide TiC, a silicon carbide SiC, a boron carbide B4C, or the like, or ceramics such as an aluminium oxide Al2O3, a titanium oxide TiO2, a beryllium oxide BeO, or the like is used as a single substance, or a metal such as nickel Ni, Nickel chromium Ni-Cr, or the like is used. These materials are melted by the intense heat of plasma and is sprayed from an injection hole 6 toward a conical diaphragm base material 1, which is provided to face the injection hole 6 and is formed to a required shape and consists of the paper base material, in a high speed by a working gas fed from a blast hole.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention provides a method for locating a voice coil within a magnetic gear;
The present invention relates to a diaphragm for a speaker that drives the voice coil by an audio current flowing through the voice coil, and transmits the vibration to radiate sound waves into the air.

[Technical background of the invention and its problems] Conventional materials used for such speaker diaphragms have a density ρ.
is as small as possible, the elastic modulus E is approximately the same, the vibration propagation velocity is high, the frequency range is wide, the internal loss is appropriate, the damping characteristics are appropriate, etc.

Vibrators made only of pulp base material, which is the most widely used speaker diaphragm, have low rigidity because the strength is only the fibrillation and entanglement of pulp fibers.
Since the Young's modulus becomes small, the frequency band becomes increasingly narrow, and split vibrations tend to occur, making it impossible to faithfully reproduce the original sound.

[Purpose of the invention]

In order to eliminate the drawbacks of the conventional pulp-based speaker diaphragms as described above, the present invention provides non-oxide ceramics alone, metals, By spraying metal oxide as a matrix, the rigidity of the diaphragm is increased, Young's modulus is increased, the frequency bandwidth is wide, split vibration is less likely to occur, and the original sound can be easily reproduced faithfully.A diaphragm for speakers. The purpose is to provide the following.

[Embodiments of the invention]

An example of the implementation of the present invention will be described below regarding a plasma spraying method shown in the drawings.

In this plasma spraying method, as shown in FIG. 1, plasma is generated using an electric arc and used as a high heat source for spraying, and the spraying material is introduced through the injection port 4.

Thermal spray materials include poron nitride BN, aluminum nitride AIN, silicon nitride 3i3N++, titanium nitride TiN.
metal nitrides such as titanium boride TiB2, metal borides such as aluminum boride A n B2, titanium carbide TiC,
Metal carbides such as silicon carbide S i C, boron carbide B, a C, aluminum oxide Al2O3, titanium oxide T
Ceramics such as iO2, helium oxide BeO, etc., or nickel Ni1 nickel chrome Ni-C
Metals such as r are used.

These materials are melted by the high heat of the plasma, and are sprayed at high speed from the injection port 6 by the working gas sent from the ventilation port 5 into a cone-shaped paper base material that is placed in the desired shape and placed opposite to the injection port 6. It is sprayed toward the vibration-like base material 1 .

The sprayed ceramic alone or the mixture with metal enters between the base material 1 and the diaphragm prototype on the back of the base material 1, and eventually a deposited layer is formed on the surface of the base material 1. Ru.

Incidentally, the above-mentioned melting of the non-oxide ceramics alone is carried out under reduced pressure or in a room kept in an inert atmosphere, or in the atmosphere, the melting is carried out using a metal or metal oxide as a matrix. Prevents decomposition and oxidation.

The non-oxide ceramics, metals, and metal oxides sprayed in this way are sprayed from both sides of the base material 1 so as to form conite surfaces 2 on both sides of the base material 1, as shown in FIG. , or as shown in FIGS. 3 and 4, it is sprayed onto one side of the base material 1 so as to form a coated surface 2 on the front or back surface.

In this way, by spraying the above-mentioned material that forms the coated surface 2 on the paper base material 1, physical properties that cannot be obtained with paper base +31 or other single materials, that is, a human-like blowfish rate can be obtained. The frequency band is extended, split vibrations are less likely to occur, the appropriate internal loss of the paper base material 1 is maintained, and a highly rigid diaphragm can be obtained.

〔Effect of the invention〕

As mentioned above, the present invention applies a metal nitride to the surface of a paper base material whose main raw material is pulp fiber by, for example, plasma spraying.
Ceramic materials such as metal borides, metal carbides, and metal oxides are melted alone or as a matrix of metals and metal oxides to form a coated surface, which has high rigidity and vibration resistance with relatively large internal loss. It can be made into a plate, and therefore, it is possible to obtain vibration treatment for a speaker that faithfully reproduces the original sound, which is difficult to produce due to split vibration, and has a wide bandwidth.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which FIG. 1 shows a state of thermal spraying by a plasma spraying method, and FIGS. 2 to 4 are sectional views of a state of coating formation.

Claims (1)

[Claims] It is characterized by spraying a metal compound such as metal nitride, metal boride, metal carbide, gold M oxide alone or in the form of a matrix of metal or metal oxide onto the surface of a paper base material formed into a desired shape. A diaphragm for speakers.