JP3947333B2 - Speaker diaphragm and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a speaker diaphragm using a woven fabric and a manufacturing method thereof.
[0002]
[Prior art]
The physical properties required for the speaker diaphragm are typically three: light weight, high elastic modulus, and high internal loss.
Conventionally used paper cone type diaphragms have a large degree of freedom in forming shape, are relatively lightweight, and have a large internal loss. On the other hand, since the elastic modulus is remarkably small and the moisture resistance is poor, many proposals for improvement have been made.
[0003]
Recently, cross cone diaphragms made by molding prepregs (semi-cured resins) of high-elasticity fibers such as carbon fibers have appeared, and a large elastic modulus can be obtained by improving moisture resistance. However, this prepreg molded body has a drawback that a lightweight diaphragm cannot be obtained with a small internal loss.
[0004]
[Problems to be solved by the invention]
Therefore, it is conceivable to bond the prepreg molded body and a paper or resin molded member previously molded into a diaphragm shape with an adhesive. As a result, it is possible to create a diaphragm having a relatively large degree of freedom in forming shape and good physical properties.
However, the number of manufacturing steps for forming both members into a diaphragm shape, bonding them with an adhesive, and cutting the periphery to form a diaphragm increases, resulting in an increase in cost.
[0005]
The present invention has been made in view of the above circumstances. A woven fabric is used as a base material and is installed in a speaker diaphragm-shaped cavity formed in an injection molding apparatus, and a resin is injected into the cavity. An object of the present invention is to provide a speaker diaphragm capable of setting sound quality and frequency characteristics by adopting a two-layer structure of cloth and resin and appropriately setting woven cloth or resin.
In addition, a variety of woven fabrics can be attached without using an adhesive by attaching a woven fabric in the cavity of the speaker diaphragm formed in the injection molding device and injecting resin into the cavity. Another object of the present invention is to provide a method for manufacturing a speaker diaphragm that can be combined with a resin without forming a prepreg.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, the speaker diaphragm according to claim 1 is formed by injection molding using a woven fabric as a base material before closing the movable side mold and the fixed side mold of the mold constituting the injection molding apparatus. The woven fabric and the resin are placed between the cavity of the speaker diaphragm formed in the apparatus and injected into the cavity formed by closing the movable side mold and the fixed side mold . It is characterized by having a two-layer structure.
The speaker diaphragm according to claim 2 is characterized in that , in the diaphragm according to claim 1, the woven fabric is sandwiched at a peripheral portion thereof.
[0007]
Thus, before the movable mold and the fixed mold of the mold constituting the injection molding apparatus are closed, the peripheral edge of the woven fabric is supported in the diaphragm-shaped cavity, and in this state The movable-side mold and the fixed-side mold are closed, resin is injected, and the mold is opened after the resin is solidified, whereby a diaphragm having a double structure of woven fabric and resin is obtained. At this time, a desired sound quality can be set by appropriately setting a woven fabric or a resin.
[0008]
The method for manufacturing the speaker diaphragm according to claim 3 is a method for manufacturing the speaker diaphragm by injection molding, and before closing the movable side mold and the fixed side mold of the mold constituting the injection molding apparatus, A step of attaching a woven fabric sandwiched in a speaker diaphragm-shaped cavity formed in an injection molding apparatus, a step of closing the movable side mold and the fixed side mold, and a step of injecting resin into the cavity It is characterized by comprising.
[0009]
As a result, it is possible to bond without using an adhesive, and it is possible to combine various woven fabrics with resin without making prepregs. A small speaker diaphragm can be manufactured.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a drawing quoted for explaining each manufacturing process in the method for manufacturing a speaker diaphragm of the present invention. In FIG. 1, reference numeral 10 denotes a mold constituting an injection molding apparatus, which includes a movable side mold 11 and a fixed side mold 12. An injection port (gate) 16 of an injection device is inserted into a part of the fixed mold 12 to inject the resin 15. Reference numeral 13 denotes a diaphragm-shaped cavity, and reference numeral 14 denotes a woven fabric (hereinafter referred to as a cloth material).
[0011]
In the above configuration, first, the cloth member 14 is mounted so that the peripheral edge portion of the cloth member 14 is sandwiched in the cavity 13 of the speaker diaphragm formed in the injection molding apparatus (FIG. 1A). Here, as the cloth material, carbon, Kepler, PBO, glass, Conex, or the like, or a mixed weave cloth material such as carbon and Kepla, PBO and glass, or the like is used. Next, the movable mold 11 and the fixed mold 12 of the mold 10 constituting the injection molding apparatus are closed, and the resin 15 is injected from an injection apparatus (not shown) (FIG. 2B). Here, polypropylene, polyethylene, or polypropylene-terephthalate resin material is used as the resin, and the temperature at this time is maintained at 150 ° C. to 300 ° C. Moreover, the temperature of the cavity surface of the mold 10 is kept at 10 ° C to 100 ° C. Further, the pressure for squeezing the mold 10 is maintained at about 80 to 200 t.
At this time, as shown in FIG. 4B, the resin filled in the cavity 13 between the movable mold 11 and the fixed mold 12 is solidified from the portion in contact with the fixed mold 10. Begins. Then, by performing mold opening at an appropriate timing, a speaker diaphragm having a two-layer structure of a cloth 14 and a resin 15 is obtained. Moreover, the cloth material 14 and the resin 15 can appropriately use predetermined ones, and depending on the combination, desired sound quality and frequency characteristics can be obtained.
[0012]
As described above, according to the present invention, the woven fabric 14 is mounted in the speaker diaphragm-shaped cavity 13 formed in the injection molding apparatus using the woven fabric 14 as a base material, and the resin 15 is injected into the cavity 13. A diaphragm having a two-layer structure of 14 and resin 15 can be provided. In addition, the sound quality and frequency characteristics can be set by appropriately setting the woven fabric or resin as necessary. Further, by attaching a woven cloth into the cavity 13 of the speaker diaphragm formed in the injection molding apparatus and injecting the resin 15 into the cavity 13, it is possible to perform bonding without using an adhesive. The woven fabric can be combined with resin without prepreg, so the manufacturing process is reduced, and no prepreg is required, so no adhesive is required and a loudspeaker diaphragm with high internal loss is obtained. Is possible.
[0013]
【The invention's effect】
As described above, the present invention has a speaker diaphragm shape formed on an injection molding apparatus using a woven fabric as a base before closing the movable side mold and the fixed side mold of the mold constituting the injection molding apparatus. mounted across into the cavity, by injecting resin into a cavity fixed mold and movable mold are formed closed, is intended to obtain a diaphragm having a two-layer structure according to the fabric and resin As a result, various woven fabrics can be combined with a resin without forming a prepreg, and can be bonded without using an adhesive, so that the number of manufacturing steps can be reduced and the cost can be reduced.
In addition, sound quality can be controlled by selecting the resin to be injected, and the desired sound quality and frequency characteristics can be set.
[Brief description of the drawings]
FIG. 1 is a drawing quoted for explaining a manufacturing process of the present invention.
[Explanation of symbols]
10 Mold 11 Movable mold 12 Fixed mold 13 Cavity 14 Woven cloth (cloth material)
15 Resin 16 Gate

Claims (3)

Before closing the mold movable mold and the fixed mold constituting the injection molding device, mounted across the cavity of the speaker diaphragm shape formed in an injection molding apparatus fabric as a substrate, a movable A speaker diaphragm having a two-layer structure of the woven fabric and the resin by injecting resin into a cavity formed by closing the side mold and the fixed side mold . The speaker diaphragm according to claim 1, wherein the woven fabric is held at a peripheral edge portion thereof. A method of manufacturing a speaker diaphragm by injection molding,
Before closing the movable mold and the fixed mold of the mold constituting the injection molding apparatus, attaching a woven fabric sandwiched in a speaker diaphragm shaped cavity formed in the injection molding apparatus;
Closing the movable side mold and the fixed side mold;
Injecting resin into the cavity;
A method for manufacturing a speaker diaphragm, comprising:

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