JP2000175289A - Diaphragm for speaker and speaker using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the stiffness, the withstanding temperature, a large input capability and a thin profile by foaming a resin that is a mixture of a modified polyphenylene oxide and resin and a polystyrene resin filled in metallic dies, making a center hole to fit a voice coil, forming a groove for connection tinsel and forming the outer circumference of the speaker to be nearly circular. SOLUTION: Prescribed amounts of the modified polyphenylene oxide and resin and the polystyrene resin are mixed, the mixture is foamed preliminarily, the mixture resin is filled in metallic dies. Foaming is implemented by using vapor and annealing is applied to the foamed resin in the metallic dies. A speaker diaphragm 11 of a flat plate shape obtained thereby has a cylindrical center hole 11a to which a voice coil is fitted, a step 11b to which a dust cap is fitted, a groove 11c and a throughhole 11d for positioning tinsel. Furthermore, a gate port for resin filling at forming is formed on the speaker diaphragm 11 at an outer circumferential side in the vicinity of the rear side of the groove 11c. Thus, the speaker with high tensile strength, compression hardness and heat deformation temperature and excellent sound pressure frequency characteristic can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a loudspeaker diaphragm used for various kinds of audio equipment and a loudspeaker using the same.

[0002]

2. Description of the Related Art FIG. 5 is a side sectional view of a conventional speaker. First, a conventional speaker diaphragm will be described.
Conventionally, speaker diaphragms used for speakers include various types such as pulp formed by hot pressing after paper making, resin formed by injection molding, or processed styrene plate which has been foamed. Things were used.

As shown in FIG. 5, the configuration of a speaker includes a magnetic circuit 1 comprising an upper and lower plate and a magnet and having a magnetic gap 1a formed therein.
, A speaker diaphragm 4 having an outer periphery coupled to the frame 2 through an edge 3, and a frame 2 coupled to an inner periphery of the speaker diaphragm 4 and having a magnetic gap 1 a of the magnetic circuit 1. It was formed with the voice coil 5 fitted. Reference numeral 6 denotes a tinsel wire having one end connected to the coil end of the voice coil 5 and the other end connected to the terminal 7 of the frame 2 for transmitting an external audio signal input to the voice coil 5 coil. is there.

[0004]

However, the above-mentioned speaker diaphragm has the following disadvantages.

That is, loudspeaker diaphragms made of pulp are often used because they are lightweight and have a relatively high Young's modulus, but they have problems in environmental characteristics such as water resistance.

[0006] In addition, the speaker diaphragm made of injection-molded resin has good environmental characteristics such as water resistance, but has a problem that the sound pressure level is lowered due to its heavy specific gravity.

In any case, since the surface thickness is thin, the bending rigidity is weak, so that it generally has to be formed in a cone shape (substantially conical shape), and the height as the cone shape makes the speaker thinner. Had a limit.

If the surface thickness is increased to increase the bending rigidity, the weight of the loudspeaker diaphragm becomes heavy and the sound pressure level is reduced. Further, if the input is increased, the loudspeaker diaphragm may exhibit abnormal resonance. There is a problem that the sound pressure frequency characteristic is disturbed and distortion is increased, so that it is impossible to increase the input.

Further, in a speaker using a foamed styrene speaker diaphragm, it is possible to increase the surface thickness due to its low specific gravity, but the flatness in the frequency characteristics is lost due to the low rigidity of the material itself. However, there has been a problem that the strain is increased at the time of a large input, and furthermore, the heat resistance of the material is low, so that the usable field is limited.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide a speaker diaphragm capable of increasing rigidity and increasing input power, and a speaker capable of being made thinner using the diaphragm. .

[0011]

In order to solve the above problems, a speaker diaphragm according to the present invention is formed by foaming a resin obtained by mixing a modified polyphenylene oxide resin and a polystyrene resin filled in a mold. Since the modified polyphenylene oxide resin is foamed in the mold, rigidity and heat resistance are improved, and an excellent speaker diaphragm having a low specific gravity can be obtained.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention improves rigidity, heat resistance temperature and specific gravity by forming a resin obtained by mixing a modified polyphenylene oxide resin and a polystyrene resin by foam molding. In addition, it is possible to provide an excellent speaker diaphragm in which the shape of the diaphragm can be freely set by a mold.

According to a second aspect of the present invention, there is provided a speaker diaphragm according to the first aspect, wherein a central hole into which a voice coil is fitted, and a tinsel wire for connecting the voice coil to the outside. A groove is formed, and a gate opening for filling the resin is provided on the outer peripheral side near the groove.The outer peripheral has a substantially circular shape, and in general molding during in-mold foaming by injection. During molding, the resin flows well downward due to gravity, and finally flows upward. For this reason, when the gate opening is raised, the specific gravity in the opposite direction of the gate opening becomes high, and the density near the gate opening becomes low. A speaker diaphragm that can be set in advance so as to obtain the weight balance of the diaphragm for the speaker and that can avoid a situation in which the conventional weight balance difference causes abnormal resonance and as a result it is difficult to increase the input, thereby increasing the input power. You can do it.

According to a third aspect of the present invention, there is provided a speaker diaphragm according to at least the second aspect, a voice coil fitted and coupled to a center hole of the speaker diaphragm, and one end of the voice coil. A frame connected to a terminal of a coil of the coil and disposed in a groove of the speaker diaphragm and having the other end coupled to the outer periphery of the speaker diaphragm via an edge through a through hole provided in the groove; And a tinsel wire connected to a terminal provided in the speaker panel, so that a speaker capable of increasing the input power can be obtained by using the speaker diaphragm according to claim 2 and a flat plate of the speaker diaphragm. This makes it possible to reduce the thickness of the speaker and improve the degree of freedom in designing the external design.

An embodiment of a speaker diaphragm of the present invention and a speaker using the same will be described below with reference to FIGS.

FIG. 1 is a front view of a flat speaker diaphragm according to an embodiment of the present invention, FIG. 2 is a sectional view thereof, and FIG. 3 is a speaker using the speaker diaphragm. FIG. 4 is a sound pressure frequency characteristic diagram.

First, a speaker diaphragm is prepared by mixing a modified polyphenylene oxide resin and a polystyrene resin by 50% each, pre-foaming the resin, filling the resin in a mold, and performing foam molding using steam. Thereafter, annealing is performed in a mold, and a flat plate-shaped speaker diaphragm 1 shown in FIGS.
1 was obtained.

According to FIG. 1, the speaker diaphragm 11 is formed in a substantially flat plate shape, and has a cylindrical central hole 11a for fitting a voice coil (described later) in the center. Reference numeral 11b denotes a step portion having a depth substantially equal to the thickness of a dust cap (described later), into which the dust cap is fitted.
11c is a groove for positioning and positioning a kinshi wire (described later);
11d is a hole for inserting a tinsel wire. Also one
Reference numeral 1e denotes a gate port for resin injection during molding, which is provided on the outer peripheral side near the back surface side of the groove 11c in which the tinsel wire is arranged. The physical properties of the speaker diaphragm 11 are shown in Table 1. In the above embodiment, the expansion ratio was set to 5 times. In addition, the conventional product used what processed the foamed styrene board and used it as the diaphragm for speakers.

[0019]

[Table 1]

As apparent from Table 1, the tensile strength of the embodiment is twice as high as that of the conventional product, and the compression hardness is as high as 5 times that of the conventional product. It was also confirmed that the heat deformation temperature was significantly higher at 120 ° C. than the conventional product at 75 ° C.

Using the speaker diaphragm 11 obtained as described above, a speaker having a diameter of 20 cm shown in FIG. 3 was manufactured.

In the speaker, a voice coil 18 is fitted into a magnetic gap 17 of a magnetic circuit 16, and the voice coil 18
Is supported by a damper 19. Voice coil 1
The upper part of 8 is connected to the inner peripheral part of the speaker diaphragm 11, and the outer peripheral part of the speaker diaphragm 11 is fixed to the frame 21 via the edge 20. The lead wire of the voice coil 18 is the dust cap 22 of the speaker diaphragm 11.
Is connected to the tinsel wire 23 at the step 11b into which it fits, and is fitted into the groove 11c of the speaker diaphragm 11, and then the hole 11d is formed.
2 coupled to the outside of frame 21 through
4 Step 1 on the upper part of speaker diaphragm 11
A dust cap 22 is fitted in 1b.

According to the above structure, the tinsel wire 23 is not seen from above the speaker diaphragm 11, so that the appearance becomes a completely flat plate-like structure, and the appearance quality can be improved.

FIG. 4 shows the sound pressure frequency characteristics of this speaker. From FIG. 4, it was confirmed that B of the present embodiment is flatter and extends to a higher frequency range than A of the speaker using the foamed styrene of the conventional product.

Further, an input resistance test was performed using the above speaker. The conventional foamed styrene material causes abnormal resonance at about 50 W due to the heavy weight of the speaker diaphragm 11 where the tinsel wire 23 is present, and the voice coil 18 contacts the magnetic circuit 16 in the magnetic gap 17. In contrast to this, it was confirmed that the device of the present embodiment can withstand a test of about 100 W without causing abnormal resonance even at a large input. Therefore, it has been confirmed that even when the speaker is made thinner, abnormal resonance is eliminated and a large input is possible.

In the injection molding, the resin flows well downward due to gravity during molding, and finally flows upward, so that the gate port is provided relatively high. The same applies to in-mold foaming by injection according to the present embodiment, but when the gate port 11e is raised, the specific gravity in the opposite direction of the gate port 11e increases, and
The density near 1e decreases. In the present embodiment, the Kinshi line 2
As described above, the relationship between the disposition position of the gate 3 and the gate opening 11e is determined as described above.
1c, the weight balance of the speaker diaphragm 11 can be obtained by the tinsel wire 23,
It is considered that the abnormal resonance disappeared and a large input became possible.

In the above embodiment, each of the modified polyphenylene oxide resin and the polystyrene resin is 50%
The mixed resin was used as the foaming material for the speaker diaphragm. However, even if the modified polyphenylene oxide resin was 30% and the polystyrene resin was 70%, almost the same heat resistance (heat deformation temperature) was about 100 ° C. The result was obtained.

[0028]

As described above, the loudspeaker diaphragm of the present invention can be formed by foaming a mixture of a modified polyphenylene oxide resin and a polystyrene resin in a mold, thereby improving rigidity and heat resistance temperature. An excellent speaker diaphragm having a light specific gravity and an excellent speaker using the same can be provided.

[Brief description of the drawings]

FIG. 1 is a front view of an embodiment of a speaker diaphragm according to the present invention.

FIG. 2 is a sectional view of the same.

FIG. 3 is a half sectional view of the speaker according to the same embodiment;

FIG. 4 is the same sound pressure frequency characteristic diagram

FIG. 5 is a sectional view of a conventional speaker.

[Explanation of symbols]

 11 Speaker diaphragm 11b Step 11c Groove 11e Gate 16 Magnetic circuit 17 Magnetic gap 18 Voice coil 20 Edge 21 Frame 23 Kinshi wire 24 Terminal

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ryuji Suzuki 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Shoji Nakajima 1006 Kadoma Kadoma City, Osaka Pref. Terms (reference) 5D016 AA01 CA03 EC00 EC04 FA01 JA03

Claims (3)

[Claims] 1. A speaker diaphragm formed by foam molding a resin obtained by mixing a modified polyphenylene oxide resin and a polystyrene resin. 2. A central hole into which the voice coil is fitted,
A groove in which a tinsel wire for connecting the voice coil to the outside is formed, and a gate opening for resin filling is provided on an outer peripheral side near the groove. The diaphragm for a speaker according to 1. 3. The speaker diaphragm according to claim 2, a voice coil fitted and coupled to a center hole of the speaker diaphragm, and one end connected to a terminal of a coil of the voice coil. The other end is connected to a terminal provided on a frame in which the outer periphery of the speaker diaphragm is connected via an edge through a through hole provided in the groove. Speaker composed of a kinshi line.