JP2001204094A - Speaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a speaker that is used as various electroacoustic transducers and employs an excellent speaker diaphragm of a high sound frequency use dome shape or the like of lightweight, having a very high internal loss and high reliability. SOLUTION: A resin film is used for a base, a foamed resin sheet, an elastomer, or a nonwoven fabric or the like is laminated on the surface of the resin film, the resulting base is heated and pressed, and formed into a desired shape, which is the speaker diaphragm 11 used for the speaker of this invention. The manufacturing process for the speaker diaphragm is simple, variation is small, and the speaker with the high frequency sound use dome shape or the like can be realized with excellent quality and excellent reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dome-shaped speaker used for various audio equipment.

[0002]

2. Description of the Related Art A conventional speaker will be described with reference to a sectional view of a dome-shaped speaker shown in FIG.

In FIG. 1, 1 is a yoke, 2 is a magnet, 3 is a top plate, and the yoke 1 and the top plate 3 form an annular magnetic air gap 4 with the magnet 2 interposed therebetween. Reference numeral 5 denotes a voice coil wound around a voice coil bobbin 6, which is suspended in the magnetic gap 4 so as to vibrate.

[0004] Reference numeral 7 denotes a dome diaphragm as a speaker diaphragm formed of a thin metal foil.
Is made of a cloth whose surface is air-permeable by applying a rubber-based resin to the surface by coating. The outer peripheral portion of the edge 8 is fixed on a spacer 9 and is sandwiched by a baffle plate 10.

The operation of the dome-shaped speaker configured as described above will be described below.

First, a voice coil 5 is suspended from the magnetic gap 4. When an electric signal is applied to the voice coil 5, a dome diaphragm is passed through a voice coil bobbin 6 via a voice coil bobbin 6 according to Fleming's left hand rule. 7 is vibrated and pronounced.

The dome-shaped dome diaphragm 7 of the loudspeaker constructed as described above is made of a film such as a polyimide film or a polyethylene naphthalate resin film alone or a rubber base material impregnated with a rubber resin in addition to the above metal foil. A processed sheet molded product is used, and a metal foil formed of titanium, aluminum, or the like is used.

[0008]

However, a speaker diaphragm obtained by molding a resin film such as the above-mentioned polyimide film or polyethylene naphthalate resin film is light in weight and has good rigidity, but has an internal loss. In this case, resonance is likely to occur due to lack of sound quality, and there remains a problem in sound quality. On the other hand, a speaker diaphragm made of a soft dome obtained by molding a sheet in which a rubber base material is impregnated with a rubber resin has a very high internal loss and enables high sound quality with little resonance, but the material is heavy, Sound pressure decreases. In addition, there are many manufacturing processes such as impregnating a thermosetting phenol resin and a rubber-based resin as a molding resin on a cloth base material, and thus there is a problem such as variation in quality.

A dome-shaped speaker diaphragm obtained by molding a metal such as titanium or aluminum has high rigidity and good elongation up to a high band (high band characteristic), but internal loss is low. Due to the small size, resonance is likely to occur, and there is a peak feeling of keen. Since the above-mentioned metal foil has a low elongation, a certain material thickness is required at the time of molding, and when it is thin, wrinkles or cracks are generated. It has disadvantages such as low sound pressure due to high specific gravity.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and provides a speaker using a dome-shaped speaker diaphragm for high sound which is lightweight, has very high internal loss, and has excellent reliability including heat resistance. It is intended to do so.

[0011]

According to the present invention, there is provided a loudspeaker comprising a resin film as a base material, and a foamed resin sheet or an elastomer or nonwoven fabric laminated on the surface of the resin film into a desired shape. A speaker is formed using the speaker diaphragm thus formed.

The speaker diaphragm has a very high internal loss and a high sound quality with little resonance. Also, when molded into a dome shape, since the laminated foamed resin and the like have a large internal loss and flexibility, when molding a speaker diaphragm, the dome can be easily formed, and the quality is stable. This makes it possible to provide a loudspeaker that has been used.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is characterized in that a resin film is used as a base material, and a foamed resin sheet, an elastomer or a nonwoven fabric is laminated on the surface of the resin film.
A speaker diaphragm obtained by pressure molding is used, and it is possible to provide a speaker having high sound pressure, little variation, good quality, and excellent reliability.

[0014] The second aspect of the present invention is the first aspect.
Polyurethane-based resin film or polyurethane-based foamed resin film or a non-woven fabric made of silk is used as a laminate on the base material of the speaker diaphragm according to the above,
A speaker using this speaker diaphragm has high sound pressure,
It is possible to provide a speaker with little variation, good quality, and excellent reliability.

The third aspect of the present invention is the first aspect of the present invention.
By using a non-stretched film as the resin film for the base material of the speaker diaphragm described in the above, taking advantage of the features of lightweight and high rigidity of the non-stretched film and a small difference in physical strength in the vertical and horizontal directions, It is possible to provide an excellent speaker diaphragm with less deformation after molding, and a speaker using the same has a high sound pressure, a small variation,
It can be of high quality and excellent in reliability.

An embodiment of the present invention will be described below with reference to FIGS.

(Embodiment 1) FIG. 1 is a sectional view of a speaker diaphragm which is a main part of a speaker according to the present invention, and FIG. 2 is a sound pressure characteristic diagram of the same frequency.

First, a substrate 1, a substrate 2, a substrate 3
In addition, a base material A for comparison, a base material B for comparison, and a base material C for comparison were prepared.

The shape of the speaker diaphragm was the shape shown in FIG. 1 and a dome shape having a diameter of 25 mm. Height is 10mm
It is.

Substrate 1 A laminated sheet material in which a polyurethane foam resin sheet was bonded and attached to a polyethylene naphthalate resin film 30 μm was used as a substrate 1. The foaming ratio of the foamed resin sheet used was 30 times. A urethane-based adhesive was used. The weight of the substrate 1 is about 65 to 70 g / m ² .

Substrate 2 A laminated sheet material obtained by laminating a 20 μm urethane resin film having excellent flexibility on a 30 μm polyethylene naphthalate resin film was used as the substrate 2. The urethane resin film can be bonded to the polyethylene naphthalate resin film during film processing, and does not require an adhesive. The weight of the substrate 2 is about 60 to 65 g / m ² .

Substrate 3 A laminated sheet material in which a nonwoven fabric made of silk or the like was attached to a polyethylene naphthalate resin film 30 μm by adhesion was used as a substrate 3. The basis weight of the nonwoven fabric is 30 g / m ² . A urethane-based adhesive was used. The weight of the substrate 3 is about 65
７０70 g / m ² .

Comparative Base Material A As an example of a conventional dome-shaped speaker diaphragm, a base material A having a polyethylene naphthalate resin film of 50 μm was obtained. The weight of the base material A is approximately 60~65g / m ^2.

Comparative Base Material B As another example of the conventional dome-shaped speaker diaphragm,
A base material B of 30 μm of aluminum metal foil (30 μm or less was impossible to form into a dome shape) was obtained. The weight of the substrate B is about 80 to 85 g / m ² .

Comparative Base Material C As another example of a conventional dome-shaped speaker diaphragm,
A sheet base material C obtained by impregnating a fabric with a rubber resin was obtained. The weight of the substrate C is about 95-100 g / m ² .

Referring to FIG. 1 for the base material for the diaphragm,
More specifically, when the speaker diaphragm 11 made of the base material 1 is formed into a dome shape, the speaker diaphragm 11 is formed by mounting a urethane foam sheet 13 on a polyethylene naphthalate film 12. Since the urethane foam sheet 13 itself has good elongation and flexibility, the speaker diaphragm 11 has good moldability due to the cushion-like effect of the urethane foam sheet 13 on the mold during molding. Become.

As the polyethylene naphthalate film 12, an unstretched film is used. Although a stretched film has an effect, the use of a non-stretched film makes it possible to provide a more excellent speaker diaphragm 11 with less deformation after molding.

Since the above-mentioned speaker diaphragm 11 is composed of the polyethylene naphthalate film 12 having an appropriate rigidity and the urethane foam sheet 13 having a high internal loss, a high-quality sound speaker with little resonance can be realized.

As for the film forming conditions, the sheet having the above-mentioned structure is heated at a temperature of 150 ° C. to 160 ° C. for 5 seconds to 10 seconds, inserted into a mold, pressed, cooled to 100 ° C. or less, and then cooled. The intended speaker diaphragm 11 can be obtained by taking out from the mold. Since the same effect can be obtained even if the material of the resin film is changed, the description is omitted.

Comparison of the physical properties, elongation, density, and moldability of the base materials 1 to 3 and the comparison base materials A to C (Table 1) shows the characteristics of the speaker using the speaker diaphragm (FIG. 1). 2)
Shown in

FIG. 2A shows a frequency sound pressure characteristic of a speaker using a speaker diaphragm made of the base material 1.
2 (b) is based on the comparative substrate A, and FIG. 2 (c) is based on the comparative substrate C.

As is apparent from FIG. 2, the speaker using the speaker diaphragm of the base material 1 has a high sound pressure, not only can reproduce the sound range up to the high range, but also has a peak in the high range. It has been confirmed that the speaker has a low distortion.

[0033]

[Table 1]

Further, as is apparent from Table 1, the speaker diaphragm according to the present embodiment has good weight, rigidity and elongation, and therefore, excellent effects can be obtained in terms of moldability. Was confirmed.

[0035]

As described above, since the speaker diaphragm used in the speaker of the present invention is formed by molding a resin film as a base material and laminating a foamed resin sheet, an elastomer, a nonwoven fabric, or the like thereon, the resonance is achieved. A high-quality loudspeaker with high quality can be provided at the same time as achieving a high-quality loudspeaker with a low sound quality, a light weight, a high sound pressure, a simple manufacturing process, and a good quality with little variation in weight.

[Brief description of the drawings]

FIG. 1 is a sectional view of a speaker diaphragm which is a main part of a speaker according to the present invention.

2A is a diagram showing a sound pressure frequency characteristic of a speaker according to the present embodiment; FIG. 2B is a diagram showing a sound pressure frequency characteristic of a conventional speaker; FIG.

FIG. 3 is a sectional view of a conventional dome-shaped speaker.

[Explanation of symbols]

 11 diaphragm for speaker 12 polyethylene naphthalate film 13 urethane foam sheet

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Goro Tsuchiya 1006 Kazuma Kadoma, Kazuma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 5D016 AA08 AA14 CA05 CA08 DA01 EA02 EC11 FA03 JA06

Claims (3)

[Claims] 1. A loudspeaker using a loudspeaker diaphragm obtained by heating and pressing a resin film as a substrate and laminating a foamed resin sheet or an elastomer or a nonwoven fabric on the surface as a laminate on the substrate. . 2. The speaker diaphragm according to claim 1, wherein a polyurethane resin film, a polyurethane foam resin film, or a nonwoven fabric made of silk is laminated on a polyethylene naphthalate resin film which is a resin film as a base material. The described speaker. 3. The speaker according to claim 1, wherein an unstretched film is used as the resin film.