JPH0690497A - Speaker edge - Google Patents

Abstract

(57) [Summary] [Structure] A nonwoven fabric containing at least 10% by weight or more of acrylic fiber is thermocompression-molded at a temperature higher than the softening temperature of the acrylic fiber and lower than the melting temperature. [Effect] Since the hardness of the desired portion of the edge 8 can be easily changed, the performance of the edge 8 is improved, such as having flexibility that does not hinder the amplitude motion of the diaphragm and having an appropriate vibration damping property. As the result, it can meet the requirements required for
The performance of the speaker can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker, and more particularly to a speaker edge relating to the diaphragm.

[0002]

2. Description of the Related Art Generally, a speaker edge is provided between a diaphragm 9 which emits sound and a frame 7, as shown in FIG. For the edge, for example, a woven or non-woven fabric impregnated with a thermosetting resin such as phenol resin and dried, and then molded into a desired shape by hot press molding,
Alternatively, a urethane foam may be molded into a desired shape by heat-pressing it into a substantially semicircular shape.

[0003]

By the way, normally, the speaker edge has a desired shape, and has flexibility that does not hinder the amplitude movement of the diaphragm.
It is required to satisfy requirements such as having a proper vibration damping property.

However, in the case of an edge formed by using a thermosetting resin such as a phenol resin as described above, a desired shape can be obtained by thermocompression molding, and the edge is formed by hardening the resin. Although it can be held with, on the other hand, since the entire edge is hardened,
There is a problem that it is not possible to obtain sufficient flexibility of the edge, and thus it is not possible to obtain sufficient vibration damping property for the vibration from the diaphragm. Further, there is a problem that the performance of the edge varies due to the variation in the impregnated amount of the phenol resin or the like.

Further, in the case of an edge formed of a urethane foam in a substantially semicircular shape, flexibility and appropriate vibration damping can be obtained, but when the shape is unitary and the rigidity of the edge is uniform. As a result, resonance occurs with the diaphragm at a specific frequency over the entire circumference of the edge, and in the frequency characteristics of the speaker using the edge, for example, as shown by the broken line in FIG. There is a problem that peaks or dips can be seen.

Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide flexibility that does not hinder the amplitude motion of the diaphragm and appropriate vibration damping property, and further to provide a specific frequency. Another object of the present invention is to provide a speaker edge that can be used as a speaker in which no significant peak or dip occurs.

[0007]

A speaker edge according to claim 1, wherein a nonwoven fabric containing at least 10% by weight or more of thermoplastic resin fiber is higher than the softening temperature of the thermoplastic resin fiber and higher than the melting temperature. Is characterized by being hot pressed at a low temperature.

According to a second aspect of the present invention, in the loudspeaker edge according to the first aspect, the loudspeaker edge is heat-press molded by a molding die in which a molding cavity thickness is partially and continuously changed. It is what

According to a third aspect of the invention, the speaker edge is characterized in that an uneven pattern is formed on the surface.

The speaker edge according to claim 4 is characterized in that the texture pattern of the inorganic fiber woven fabric is copied and formed on the surface by thermocompression molding through the inorganic fiber woven fabric. is there.

[0011]

According to the constitution of claim 1, since the thermoplastic resin can be melted by pressing into a fine fibrous form even at a melting temperature or lower, it contains at least 10% by weight or more of the thermoplastic resin fiber. When the non-woven fabric to be hot-press molded at a temperature higher than the softening temperature of the thermoplastic resin fiber and lower than the melting temperature, the heat contained in the non-woven fabric is partially changed by changing the pressure at a desired site. The plastic resin fibers can be partially melted.
Further, in the edge formed by hot pressing as described above, the portion that is solidified after melting is harder than the portion that is solidified without melting, so that the hardness of the desired portion of the edge can be freely changed. Therefore, not only can the desired shape that is the requirement for the speaker edge be retained, but also the flexibility that does not hinder the amplitude movement of the diaphragm, which has not been obtained with the thermosetting resin up to now, is appropriate. It is also possible to satisfy the requirement that it has a good vibration damping property. Further, since treatment such as impregnation with a thermosetting resin is not required, it is possible to form a stable edge with no variation in performance by a simple method, and consequently improve the performance of the speaker. be able to.

According to the structure of claim 2, by partially and continuously changing the molding cavity thickness in the molding die for molding the edge, the edge woven fabric arranged in the molding cavity according to the molding cavity thickness. The pressure on the cloth or nonwoven can be partially varied. That is, the pressure in the thin portion of the molding cavity is higher than the pressure in the thick portion. Therefore, for example, when molding a thermoplastic resin fiber contained in a nonwoven fabric as described above,
Higher than the softening temperature of the thermoplastic resin fiber used here, by thermocompression molding at a temperature lower than the melting temperature, the thermoplastic resin fiber is melted in the thin molding cavity portion, Since the hardness of the part is larger than that of other parts, the desired shape can be maintained, and in the part where the molding cavity thickness is thick, the thermoplastic resin fiber does not melt but stays only softened. Therefore, it is possible to have flexibility that does not hinder the amplitude motion of the diaphragm and to have appropriate vibration damping properties. That is, the three required for the above-mentioned speaker edge.
It can meet all one requirement. Furthermore, the pressure applied to the edge non-woven fabric can be easily changed only by changing the thickness of the molding cavity, so that the speaker edge having a desired shape and having no variation in performance can be easily manufactured.

According to the third aspect of the present invention, the thickness of each part of the edge can be made different by forming an uneven pattern on the edge surface made of a foamed resin such as urethane foam. The rigidity can be non-uniform. Therefore, since the frequency that resonates with the diaphragm can be dispersed at each part of the edge, the resonance of the diaphragm and the edge can be suppressed, which suppresses the occurrence of a remarkable peak or dip in the frequency characteristic of the speaker. As a result, it is possible to improve the performance of the speaker using such an edge with uneven rigidity.

According to the structure of claim 4, an edge made of a foamed resin such as urethane foam is thermocompressed through the inorganic fiber woven cloth to form a texture pattern of the inorganic fiber woven cloth on the edge surface. Since the copy can be formed, the edge surface can be more easily formed into an uneven shape. Therefore, the texture of the edge makes the rigidity of the edge non-uniform, and resonance of the diaphragm and the edge can be suppressed, so that it is possible to suppress the occurrence of a remarkable peak or dip in the frequency characteristic of the speaker. Further, since the rigidity of the edge can be made non-uniform only by hot pressing through the inorganic fiber woven cloth, the speaker edge can be manufactured more easily and cheaply.

[0015]

[Embodiment 1] The following will describe one embodiment of the present invention in reference to FIG. 1, FIG. 2 and FIG.

As shown in FIG. 5, the speaker according to the present embodiment comprises a magnetic circuit section 1 and a vibrating section 2, of which the magnetic circuit section 1 is a circular flat plate portion 3a and this flat plate portion 3a. Support plate 3 formed of a cylindrical center pole 3b provided in the center of the magnet, an annular magnet 4 fixed to the center pole 3b side of the flat plate portion 3a concentrically with the center pole 3b, and an upper end surface of the magnet 4. And an annular upper plate 6 concentrically provided with the magnet 4. The air gap formed between the magnet 4 and the upper plate 6 and the center pole 3b is used as a magnetic gap to guide the magnetic flux from the magnet 4 to the voice coil 5 described later.

The vibrating section 2 has a vibrating plate 9 in the shape of a cone, and a voice coil 5 as a vibrating source is provided in a central hole portion of the vibrating plate 9 which is the top of the cone.
The voice coil bobbin 5a is fixed by adhesion or the like. Then, a flexible annular damper 11 is fixed to the voice coil 5 and the diaphragm 9 by adhesion or the like,
The outer peripheral portion of the damper 11 is elastically supported by a conical frame 7 fixed to the upper end surface of the upper plate 6 by adhesion or the like. On the other hand, an edge 8 is adhered to the outer circumference of the cone bottom of the diaphragm 9, and the edge 8 is fixed to the edge support portion 7a of the frame 7 by adhesion or the like. That is, the frame 7 also supports the diaphragm 9 via the edge 8. Further, a dust cap 10 for preventing dust is provided on the voice coil 5 side of the diaphragm 9.

The edge 8 is hot-press molded by molding dies 21 and 22, as shown in FIG. 1 (a). An edge 8 is formed on the mating surface of the molding dies 21 and 22.
A molding cavity 23 corresponding to the outer shape of is formed. As shown in FIG. 1 (b), the molding cavity 23 has a thickness B of the outer peripheral portion 8b and the inner peripheral portion 8c which are the brim portions of the edge 8 which is heat-press molded by the molding dies 21 and 22. Is 0.2 mm, and the edge roll portion 8a
Is adjusted to have a thickness A of 0.5 mm.

In the molding dies 21 and 22, a non-woven fabric having a basis weight of 200 g / m ² containing 20% of a thermoplastic resin fiber, for example, an acrylic fiber having a fiber diameter of 2 denier, is applied to the acrylic fiber at a softening temperature (120 ° C.). ) Higher than the melting temperature (230 ° C.) and lower than 160 ° C. by hot pressing to obtain the edge 8.

By the way, the fibers made of a thermoplastic resin such as acrylic resin can be melted by increasing the pressure even at a temperature not higher than the melting temperature, and the degree of this melting is almost proportional to the acting pressure. As described above, if the hot press molding is performed at a temperature equal to or lower than the melting temperature, it is possible to partially melt the resin by partially changing the pressure. That is,
The hardness of the desired portion of the edge can be freely changed. Therefore, in the present embodiment, as described above, the edge 8
The pressure applied to each of A and B is adjusted by adjusting the thickness B corresponding to the brim portion to be smaller than the thickness A corresponding to the edge roll portion 8a. As a result, the molding cavity 2
3 where the molding cavity is thin, that is, edge 8
Since the molding pressure in the portion corresponding to the outer peripheral portion 8b and the inner peripheral portion 8c is larger than the molding pressure in the portion having a large molding cavity thickness, that is, the portion corresponding to the edge roll portion 8a, after the molding, In the portion 8b and the inner peripheral portion 8c, the acrylic fiber melts and acts as a binder for other fibers to increase the hardness, while the edge roll portion 8a does not apply a large pressure, so the acrylic fiber is not melted. However, since it remains only softened, the hardness shows almost the same as before molding and shows flexibility.

From this fact, the outer peripheral portion 8b, which is a peripheral brim portion which is a joint portion between the edge 8 and other speaker components.
In addition, since the hardness of the edge 8 is large in the inner peripheral portion 8c, the edge 8 can be held in a desired shape, and the edge roll portion 8a involved in the speaker amplitude movement of the edge 8 has a conventional thermosetting property. Since it is possible to obtain sufficient flexibility that does not hinder the amplitude movement which has not been obtained with the organic resin, it is possible to maintain an appropriate vibration damping property.

That is, required for the speaker edge,
It satisfies all three requirements of maintaining a desired shape for the speaker, having flexibility so as not to interfere with the amplitude movement of the speaker diaphragm, and having an appropriate vibration damping property. Further, in a speaker using such a speaker edge, as shown in FIG. 2, a stable sound pressure level can be obtained if the frequency to be reproduced is a certain value or more. Therefore, the performance of the speaker can be improved. Furthermore, by using a non-woven fabric in which a thermoplastic resin is thinned and contained in a fibrous form, it is unnecessary to impregnate a woven fabric or a non-woven fabric with a thermosetting resin as in the conventional case, and therefore, the edge Is more convenient to manufacture. Further, variations in edge performance due to variations in impregnated amount are eliminated, and an inexpensive and stable speaker edge can be provided.

In this example, acrylic fiber was used as the thermoplastic resin fiber, the thickness B of the molding cavity was 0.2 mm at the brim of the edge, and the thickness A of the edge roll 8a was 0.5 mm. However, the present invention is not limited to this as long as the above effects can be obtained.

[Embodiment 2] Another embodiment of the present invention will be described below with reference to FIGS. 3 to 5.

The speaker according to this embodiment uses the edge 18 shown in FIG. 3 (b) instead of the edge 8 shown in FIG. 5, and the other components are the same as those in the first embodiment. The description is omitted.

As shown in FIG. 3 (a), the edge 18 is thermocompression-molded by molding dies 31 and 32. A molding cavity 33 corresponding to the outer shape of the edge 18 is formed on the mating surfaces of the molding dies 31 and 32, and a material of the edge is formed, for example, through a carbon woven cloth 34 which is an inorganic fiber woven cloth. By heat-pressing the urethane foam, a weave pattern of carbon woven cloth is transferred and formed on the surface 35 of the edge 18, as shown in FIG. 3B.

Therefore, the caliber 1 using the above-mentioned edge 18
The frequency characteristics of the 0 cm speaker are shown in FIG. Incidentally, the broken line is the same shape and the same material as in the present embodiment, and at the time of edge formation, hot press molding was performed without interposing a carbon woven cloth,
It is assumed that the frequency characteristics of the comparative example due to an edge having uniform rigidity are shown.

Here, the frequency characteristic indicated by the broken line is about 2
It can be seen that a peak due to edge resonance and a dip due to reverse resonance occur around 000 Hz. On the other hand, in the frequency characteristics of the speaker using the edge according to the example, such peaks and dips are not recognized.

That is, the edge 1 formed as described above
In FIG. 8, an uneven weave pattern is formed on the surface 35, and since the thickness of each of the concave and convex portions is different, the rigidity of the edge 18 becomes uneven, and the frequencies of resonance generation of the edge 18 are dispersed. You can Therefore, resonance between the diaphragm 9 and the edge 18 is eliminated, and it is possible to suppress the occurrence of a remarkable peak or dip in the frequency characteristic of the speaker.

Therefore, the speaker using the edge 18 having uneven rigidity as described above has excellent frequency characteristics and excellent acoustic characteristics.

Further, since it is possible to easily form an uneven pattern on the surface 35 of the edge 18 simply by thermocompressing the urethane foam with a carbon woven fabric interposed therebetween, it is possible to easily and inexpensively achieve high performance. The speaker edge of can be manufactured.

In this embodiment, the carbon woven fabric is used as the inorganic fiber woven fabric, but the woven fabric is not limited to this as long as the above effects can be obtained.

[0033]

As described above, in the speaker edge according to claim 1, the nonwoven fabric containing at least 10% by weight or more of the thermoplastic resin fiber has a melting temperature higher than the softening temperature of the thermoplastic resin fiber. It is characterized in that it is subjected to thermocompression molding at a lower temperature.

Therefore, since the hardness of the desired portion of the edge can be easily changed, in addition to maintaining the desired shape, the amplitude of the vibration plate which has hitherto been impossible to obtain with the thermosetting resin. It is possible to satisfy the requirements of having flexibility that does not hinder movement and having appropriate vibration damping properties. In other words, it is possible to meet all the requirements necessary for improving the edge performance, and to eliminate the variation in the amount of impregnation that has occurred when impregnating the thermosetting resin and the variation in the performance of the edge that occurs, and to obtain a stable edge. And the performance of the speaker can be improved.

According to a second aspect of the present invention, the speaker edge is heat-press molded by a molding die in which the molding cavity thickness is partially and continuously changed.

Therefore, in addition to the effect of claim 1, the hardness at each part of the edge can be easily changed only by changing the thickness of the molding cavity of the molding die, so that the performance of the edge can be improved by a simpler method. It is possible to improve the sound quality, and as a result, it is possible to improve the performance of the speaker.

According to a third aspect of the present invention, the speaker edge has an uneven pattern formed on its surface.

Therefore, since the thickness of the edge can be made different in each part by forming the uneven pattern on the edge surface, the rigidity of the edge can be made non-uniform, and the resonance frequency of the edge can be reduced. It is possible to disperse and suppress the occurrence of peaks or dips on the frequency characteristics, and it is possible to obtain a speaker having excellent acoustic characteristics with excellent frequency characteristics.

According to a fourth aspect of the present invention, the speaker edge is characterized in that the texture pattern of the inorganic fiber woven fabric is copied and formed on the surface by thermocompression molding through the inorganic fiber woven fabric. .

Therefore, it is possible to form an uneven surface having a texture pattern on the surface of the edge only by heat-pressing the edge by interposing the woven inorganic fiber cloth between the molding dies, so that it is easy and inexpensive. The rigidity of the edge can be made non-uniform, the resonance frequency of the edge can be dispersed, the occurrence of peaks or dips on the frequency characteristic can be suppressed, and the speaker has excellent acoustic characteristics with good frequency characteristics. There is an effect that can be.

[Brief description of drawings]

FIG. 1 shows a speaker edge according to an embodiment of the present invention, wherein FIG. 1 (a) is a schematic sectional view of a molding die for molding the edge, and FIG. FIG. 3 is a schematic cross-sectional view showing an edge formed by the forming die.

FIG. 2 is a graph showing frequency characteristics of a speaker using the speaker edge shown in FIG.

FIG. 3 shows a speaker edge according to another embodiment of the present invention, wherein FIG. 3 (a) is a schematic sectional view of a molding die for molding the edge, and FIG. [Fig. 3] is a schematic cross-sectional view showing an edge formed by the forming die.

FIG. 4 is a graph showing frequency characteristics of a speaker using the speaker edge shown in FIG.

FIG. 5 is a vertical sectional view showing a structure of a speaker according to each embodiment of the present invention.

[Explanation of symbols]

 8 edges 18 edges 21 molding dies 22 molding dies 23 molding cavities 31 molding dies 32 molding dies 33 molding cavities 34 carbon fiber woven fabrics (inorganic fiber woven fabrics) 35 edge surfaces

Claims (4)

[Claims] 1. A non-woven fabric containing at least 10% by weight of a thermoplastic resin fiber is thermocompressed at a temperature higher than the softening temperature of the thermoplastic resin and lower than the melting temperature. And speaker edge. 2. The speaker edge according to claim 1, wherein the speaker edge is heat-pressed and molded by a molding die in which a molding cavity thickness is partially and continuously changed. 3. An edge for a speaker, wherein an uneven pattern is formed on the surface. 4. An edge for a speaker, wherein the texture pattern of the inorganic fiber woven fabric is copied and formed on the surface by hot press molding through the inorganic fiber woven fabric.