JP3134626B2 - Speaker braking cloth and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a loudspeaker brake cloth used for audio output equipment and the like.

[0002]

2. Description of the Related Art In recent years, in the audio-related industry,
With the digitalization of reproduced music sources, there is a demand for a speaker as an audio output device to have higher sound quality than before.

Conventionally, the purpose of the speaker damping cloth is to control the resonance frequency Q0 by giving a resistance to the diaphragm by suppressing the flow of air from the back of the diaphragm.
If the flow rate of the air is not uniform, there is a problem that a constant acoustic characteristic cannot be obtained.

[0004]

[0006] Conventionally, a nonwoven fabric for a speaker made of a nonwoven fabric, which is widely used, has a nonuniform aperture ratio per unit area because constituent fibers are randomly distributed. For example, when handling a small-level acoustic signal such as a micro speaker, a minute change in the flow rate of air caused by non-uniformity of the nonwoven fabric cannot be ignored. For this reason, Q0 in the acoustic characteristics is not stable, which has been a factor that greatly affects the sound quality.

[0005] When a non-woven fabric is used as a braking cloth, a slight adjustment of the flow rate is performed by using a non-woven fabric instead of a non-woven fabric due to manufacturing problems.
It has relied heavily on changing the area of the air holes formed in the speaker unit body. However, in this method, it is necessary to change the design of the ventilation hole every time the members constituting the unit are changed, and it is difficult to perform a comparative test in which Q0 is arbitrarily changed in a hearing test.
Lack of flexibility in speaker development.

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a loudspeaker brake cloth which can select an arbitrary aperture ratio by using the same material and differ in molding pressure and has a constant flow rate.

[0007]

In order to achieve the above object, a speaker braking cloth according to the present invention has a lattice-like structure in which fibers formed by coating a surface with a thermoplastic polymer resin are formed between fibers. A material obtained by heating and melting only the coating resin of a cloth woven so that the voids have a precisely constant area, adjusting the press pressure to an arbitrary opening ratio, and then cooling and solidifying the material as a braking cloth It is.

[0008]

According to this structure, the thermoplastic polymer resin coated on the fiber surface is melted by hot pressing at the time of molding and then solidified by cooling, thereby maintaining the binding force between the fibers and forming a uniform lattice. In addition to preventing misalignment of precisely woven cloth, adjusting the press pressure in the above process allows the required amount of polymer resin to flow out into the lattice created between the fibers, creating air holes. It can be set to any area. Therefore, with the change of the speaker member,
The required aperture ratio can be adjusted. Since the flow rate is always constant due to the precision as a characteristic of the woven fabric, a speaker having a stable Q0 in acoustic characteristics can be obtained.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will now be described with reference to the accompanying drawings.

The braking cloth for a speaker according to one embodiment of the present invention is obtained by compressing, heating, and melting a woven cloth of a precision woven fabric made of fibers having a surface coated with a thermoplastic polymer resin in a mold, followed by cooling and solidification. It was molded into a unique shape. This speaker braking cloth is attached so as to cover an air hole provided on the back surface of the speaker unit.

The operation of the loudspeaker configured as described above will be described below. The speaker includes a vibration system such as a diaphragm, a voice coil bobbin, and a voice coil, and a magnetic circuit system including a magnet, a pole, a plate, and a yoke. When a voice current flows through a voice coil in a uniform magnetic field, a vertical electromagnetic force is generated in the voice coil, and the voice coil vibrates according to the current. This vibration is transmitted as a sound wave by properly transmitting the vibration to the diaphragm.

Next, a method of manufacturing a braking cloth for a speaker will be described. In spinning, a woven cloth made of polyester fiber coated with a low-melting polyester resin is melted or decomposed in a mold in a mold. Heated to a temperature at which only the coated low-melting polyester resin melts, adjusted to a pressure that generates air holes with the specified flow rate, cooled and solidified, and molded into a predetermined shape with a braking cloth. did.

As described above, according to the present embodiment, a woven fabric using fibers coated with a thermoplastic polymer resin is set to a temperature at which only the coating resin is melted, and is heated and melted in a mold. The speaker using the braking cloth obtained by cooling and solidifying after adjusting the pressure to generate an air hole with a flow rate of is constant Q0, and compared with the braking cloth using a nonwoven fabric of the same shape. As a result, the variation in Q0 can be greatly reduced.

Further, since the correlation between the opening ratio of the air holes and the pressure at the time of molding can be obtained, the opening ratio can be arbitrarily changed from 0% to about 50% by adjusting the pressure.

[0015]

As described above, the speaker control according to the present invention is described.
For moving cloth , only the coating resin part of the woven fabric made of fibers coated with a thermoplastic polymer resin on the surface is heated and melted in a mold, the opening ratio of air holes is adjusted by pressure, and then cooled and solidified. Is used as a braking cloth, and the molding process is simple, and at the same time, a constant Q0 without variation is obtained, and a braking cloth having a different aperture ratio is arbitrarily selected. Thus, Q0 according to the request can be easily realized.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-43000 (JP, A) Japanese Utility Model Showa 58-164390 (JP, U) Japanese Utility Model Utility Model Showa 62-112295 (JP, U) (58) Field (Int.Cl. ⁷ , DB name) H04R 9/02 101 B29C 51/42 D03D 1/00 D06M 15/00 H04R 31/00

Claims (3)

(57) [Claims] 1. A woven fabric of fibers formed by coating a surface with a thermoplastic polymer resin, wherein the woven fabric is provided on a speaker unit.
Loudspeaker brake cloth used for the vent hole . 2. The loudspeaker brake cloth according to claim 1, wherein the amount of the heat-melted coating resin flowing out into the space between the fibers is adjusted by the press pressure to arbitrarily control the opening ratio of the woven cloth. . 3. The method according to claim 1, wherein the woven fabric is heated in a mold, and only the coating resin of the surface layer is melted and solidified by cooling.