JPS5819917Y2 - Diaphragm for speakers - Google Patents

Description

[Detailed description of the invention] This invention relates to the structure of a diaphragm for a speaker, and it is a diaphragm that suppresses peaks near the upper limit frequency, has moderate rigidity, low internal loss, and is lightweight. That's what you're trying to get.

Conventionally, speaker diaphragms made of fibrous material such as paper pulp and shaped into a frustoconical shape have been widely used because they maintain an appropriate balance of rigidity, density, and internal loss, and can be made under arbitrary conditions. Come on.

As the output increases and the playback frequency range expands, the Young's modulus is raised and a peak near the treble limit frequency occurs.As a way to suppress this peak, it is necessary to increase the vibration loss near the center of the diaphragm. The method of applying paint has been used, but although it has the effect of suppressing peaks, it does not provide rigidity to the diaphragm body.

If the paper around the diaphragm is made thicker to give it more rigidity, the diaphragm itself becomes heavier, the papermaking process takes longer, and mass productivity is poor, and there are many irregularities in papermaking.

There is a method of pasting paper on the back side of the diaphragm base, but the process is complicated and the rigidity is poor, but there are disadvantages in that vibration loss is low.

The present invention was devised to eliminate the above-mentioned drawbacks, and to explain the embodiment shown in the drawings, as shown in Fig. 1, the center of the truncated cone is made thinnest, and the center part of the truncated cone is made thinner, and This is a diaphragm for a speaker obtained by attaching a hard foamed urethane resin layer 1, which is gradually thickened and thickest at the outer periphery, to one or both sides of a fibrous diaphragm base 20 formed into a truncated conical shape.

To attach the hard foamed urethane resin layer 1 to the diaphragm base 2, as shown in FIG. The gap between the lower mold 3 and the upper mold 4 is the narrowest near the center, and gradually widens from the center to the periphery, and is widest near the periphery. 5
A plurality of pouring holes 6 are provided in the top surface of the upper mold 4, and a plurality of air discharge bends 7 are provided in the peripheral portion.

A reactive hard urethane resin of foam-in-place type is poured through the pouring hole 6 to fill the gap 5 and foam in-place, thereby attaching the hard foam urethane resin layer 1 to the diaphragm base 2.

Since the diaphragm of the present invention has the above-mentioned structure, it is lightweight, has excellent rigidity, and has excellent internal loss, expands the playback frequency range, and suppresses peaks near the treble limit frequency. It is an effective idea that has a simple manufacturing process and can be mass-produced.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of the diaphragm of the present invention, and FIG. 2 is a sectional view of a mold for manufacturing the diaphragm of the present invention. 1 is a resin layer, 2 is a base, 3 is an upper mold, 4 is a lower mold, 5 is a gap, 6 is a hole, and 7 is a bend.

Claims (1)

[Scope of utility model registration request] A fibrous diaphragm base 20 in which a hard foamed urethane resin layer 1 is formed into a truncated cone shape, with the center part of the truncated cone being the thinnest, gradually thickening from the center toward the outer periphery, and the outer periphery being the thickest. A diaphragm for speakers that can be attached to one or both sides.