JPS58157294A - Diaphragm for speaker - Google Patents

Abstract

PURPOSE:To obtain diaphragms of various kinds and different applications easily, by forming the diaphragms with the injection molding of a high elastic material where short fibers are kneaded in a thermoplastic resin. CONSTITUTION:High elasticity is attained by kneading high elastic fibers such as metallic fibers and glass fibers to a base matrix made of polypropylene or the like for the diaphragm 2, and the injection molding is executed with short reinforced fibers. Thus, the combination between the base material and the reinforced member is executed freely with the manufacture of kneaded pellets only. Thus, the reinforced member is made composite with the recombination of the kneaded pellets of the suitable same base member, allowing to form the diaphragms of various kinds and different applications easily.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inexpensive and high-performance speaker diaphragm.

Thermoplastic resins have long been used as diaphragms for speakers because they are available at low cost and are easy to process. Polypropylene, polyester, etc. have been used as resins, but conventionally all sheet-like materials have been formed into diaphragms by vacuum forming as shown in Figure 1, and other heat forming methods have been used. Because it is well-molded, the wall thickness tends to be uneven, making it difficult to obtain uniform performance.

In addition, when forming a reinforcing lip, which is usually called corrugation, the elongation rate of this part is very large compared to other parts, so the wall thickness becomes too thin, making it impossible to achieve the initial reinforcement purpose. There wasn't.

Furthermore, sheet-like materials do not necessarily have physical properties necessary for use as a diaphragm, as the original purpose of sheet production is for packaging cases or design purposes.

This invention was made in order to eliminate the above-mentioned conventional drawbacks, and by forming a diaphragm by injection molding of a highly elastic material made by kneading known fibers into a thermoplastic resin, high elasticity can be achieved at low cost. An object of the present invention is to provide a speaker diaphragm having the following features.

Embodiments of the speaker diaphragm of the present invention will be described below with reference to the drawings. FIG. 2 is a sectional view showing the structure of one embodiment of the present invention, and shows a speaker diaphragm 2 formed by injection molding.

Since this speaker moving plate 2 is made by injection molding, it is possible to express the design value shape determined by the mold shape.

This speaker diaphragm 2 has high elasticity by kneading high elastic fibers such as metal fibers or glass fibers into a base matrix such as polypropylene or polyester, and the length of reinforcing fibers is shortened (5 This injection molding method allows for the production of mixed wire pellets only, allowing for any combination of paste material and reinforcing material, and for the production of kneaded pellets of the same base material. It has the advantage that it is possible to easily obtain a wide variety of diaphragms for different purposes, such as by remixing the materials and by combining the reinforcing materials.

In addition, since injection molding is possible, it is possible to perform embossment to improve adhesion without only mold engraving, placing reinforcing ribs without causing uneven wall thickness, and sharpening without sagging on the surface. Design processing can be easily achieved.

When carrying out injection molding, a problem is warping due to the stress of the extruded part when removing it from the mold, but this can be seen in the bottom view of Figure 3 and the partially taken out sectional view of Figure 4. This problem can be solved by making the lip 4 thicker in some areas and forming the lip 4 in a tapered shape so that the stress is evenly distributed on the angle.

Furthermore, as shown in FIG. 5, it is possible to perform reinforcement processing only on the base that does not affect the surface design of the speaker diaphragm 2, and it is possible to form a lip 3 on the back surface.

Furthermore, surface images, letters, and patterns may be made to protrude only on the surface of the speaker diaphragm 20, or a reinforcing lip 3 may be raised on the surface, and these trademarks, letters, and patterns may be formed on the surface. You can.

As described above, according to the speaker diaphragm of the present invention,
Since the speaker diaphragm is formed by injection molding of a highly elastic material made by kneading short fibers with thermoplastic resin, it is possible to easily obtain diaphragms for a wide variety of purposes and to eliminate uneven wall thickness. This eliminates the irradiance and provides uniform performance.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional speaker diaphragm, FIG. 2 is a sectional view of one embodiment of the speaker diaphragm of the present invention, and FIG. 3 is another embodiment of the speaker diaphragm of the present invention. bottom view of
FIG. 4 is a cross-sectional view of the lip portion for stress dispersion in FIG. 3, and FIG. 5 is a cross-sectional view of the lip portion on the back side in FIG. 4. 2...Speaker diaphragm, 3,4...Rep,
The same reference numerals in the figures indicate the same or corresponding parts. Agent Shin Kuzuno - Figure 1 Figure 2 Figure 4 Figure 5

Claims (6)

[Claims] (1) A reinforcing filament that increases the elastic modulus is mixed with a thermoplastic resin, and the length of this filament is molded by injection molding using a kneaded material with a length of 5 mm or less so that injection molding is possible. A speaker diaphragm featuring: (2) The speaker diaphragm according to claim 1, wherein only the edges, voice coil, and other parts to be bonded are textured by mold engraving. (3) The speaker diaphragm according to claim 1, characterized in that only the Ik surface is molded with a reinforcing lip protruding by mold engraving. (4) Form a protruding part by protruding the product extrusion part from the mold after molding on the back side, and gradually reduce the wall thickness from this protruding part to the periphery, or increase the height or width of the protruding part. A diaphragm for a speaker according to claim 1, characterized in that ribs are formed that gradually decrease. (5) A diaphragm for a speaker according to claim 1, characterized in that a trademark, letters, or pattern is made to protrude only on the surface of the diaphragm. (6) A diaphragm for a speaker according to claim 1, characterized in that a trademark, characters, or a pattern is projected on the front surface of the diaphragm, and a reinforcing lip is projected on the back surface of the diaphragm.