JP2004364058A - Speaker - Google Patents

Abstract

Joule heat generated by current flowing through a voice coil is transmitted to a diaphragm via a bobbin, thereby preventing the diaphragm from being thermally deformed or a portion connected to the bobbin from falling off.
A cylindrical portion (33) is formed at a center portion of a damper (21). The cylindrical portion (33) is fitted on the outer peripheral surface of a bobbin (15). The peripheral portion 32 of the opening 31 of the diaphragm 20 is fitted and fixed by a common adhesive.
[Selection diagram] Fig. 4

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a loudspeaker, and more particularly to a loudspeaker in which a bobbin around which a voice coil is wound is joined to a peripheral portion of a central opening of a diaphragm.
[0002]
[Prior art]
A speaker widely used as a sound signal reproducing means has a voice coil wound around an outer periphery of a bobbin, the voice coil is arranged in an air gap in a magnetic circuit of a driving unit, and a sound signal current is supplied to the voice coil. By flowing, an axial force is generated on the bobbin, and this force is transmitted to a diaphragm coupled to the bobbin. Therefore, the diaphragm vibrates according to the axial force applied to the voice coil, and reproduces sound.
[0003]
FIG. 6A shows a structure of a joint between a bobbin 1 and a diaphragm 2 in a conventional speaker. The edge 3 of the opening on the center side of the cone-shaped diaphragm 2 is bonded to the damper 4 and the adhesive 5 at the outer peripheral portion of the bobbin 1. That is, the damper 4 flexibly supports the central portion of the bobbin 2 and the bobbin 1.
[0004]
In Japanese Patent Application Laid-Open No. 9-224298, the inner peripheral end of the neck portion of the center hole of the damper is formed in a tapered shape, a cut is provided in the periphery, and the tapered inner peripheral end is bent downward. A speaker is disclosed in which a damper is formed, and an inner peripheral end thereof is used as a bonding surface with a voice coil to obtain a large bonding area, thereby improving the bonding strength.
[0005]
Japanese Patent Application Laid-Open No. Sho 64-82900 discloses a speaker in which a part of a bobbin of a voice coil is formed in a corrugated or flat shape, and the molded portion is a damper.
[0006]
[Patent Document 1] JP-A-9-224298 [Patent Document 2] JP-A-64-82900 [Patent Document 3] JP-A-5-336585 [Patent Document 4] JP-A-11-146488 [ Problems to be solved by the invention]
As shown in FIG. 6A, the peripheral portion 3 of the opening on the center side of the diaphragm 2 is adhered to the outer peripheral surface of the bobbin 1 on which the voice coil is wound, with the adhesive 5 and at the same position with the damper 4 by the adhesive 5. The combined structure has a problem in that Joule heat generated by passing an electric current through the voice coil is transmitted to the diaphragm 2 via the bobbin 1, thereby increasing the temperature of the diaphragm 2.
[0007]
That is, as shown in FIG. 6B, the cone 2 is directly bonded to the bobbin 1 on which the voice coil is wound by the adhesive 5, and the heat of the voice coil is directly transmitted from the opening edge 3 of the diaphragm 2 to the center side. . In particular, when the diaphragm 2 is formed of a resin sheet such as polypropylene, the heat-resistant temperature is about 150 ° C. On the other hand, since the temperature of the voice coil at the time of the maximum input reaches around 350 ° C., the vicinity of the peripheral portion of the opening 3 on the center side of the diaphragm 2 cannot withstand such a high temperature. The central part causes thermal deformation or melting, and in some cases, the bonding of the opening edge 3 of the diaphragm 2 is released as shown in FIG. 6B, whereby the diaphragm 2 is released from the bobbin 1 and the damper 4. I will. Then, the vibration is not transmitted from the bobbin 1 to the diaphragm 2, and the diaphragm 2 does not reproduce sound. This phenomenon is remarkable when the bobbin 1 is made of a metal having excellent heat conductivity.
[0008]
The present invention has been made in view of such a problem, and in particular, heat is transmitted to a diaphragm from a bobbin on which a voice coil is wound, and the center of the diaphragm is deformed or separated from the bobbin. It is an object of the present invention to provide a loudspeaker capable of effectively preventing the loudspeaker.
[0009]
[Means for Solving the Problems]
The main invention of the present application is
In a speaker in which a bobbin around which a voice coil is wound is joined to a peripheral portion of an opening on the center side of the diaphragm,
The present invention relates to a loudspeaker, wherein a peripheral portion on a center side of a damper supporting a central side of the diaphragm is interposed between an outer peripheral portion of the bobbin and a peripheral portion of an opening on a central side of the diaphragm. is there.
[0010]
Here, a cylindrical portion is continuously provided at a peripheral portion on the center side of the damper, and the cylindrical portion is interposed between the bobbin and the peripheral portion of the opening on the central side of the diaphragm, and the bobbin and It is preferable that the peripheral portion of the opening on the center side of the diaphragm and the cylindrical portion of the damper are bonded to each other with an adhesive. Further, it is preferable that the cylindrical portion of the damper functions as a heat insulating material for preventing the transfer of heat from the bobbin to the diaphragm. Further, it is preferable that an outer peripheral edge of a cap that closes an opening of the bobbin is bonded so as to extend over a cylindrical portion of the damper and a peripheral edge of an opening on a center side of the diaphragm.
[0011]
Another main invention of the present application is
In a speaker in which a bobbin around which a voice coil is wound is joined to a peripheral portion of an opening on the center side of the diaphragm,
The present invention relates to a speaker, wherein an outer peripheral edge of a cap for closing the opening of the bobbin is interposed between an outer peripheral portion of the bobbin and a peripheral portion of an opening on the center side of the diaphragm.
[0012]
Here, a cylindrical portion is continuously provided on the outer peripheral edge of the cap, and the cylindrical portion is interposed between the bobbin and the peripheral portion of the opening on the center side of the diaphragm, and the bobbin and the diaphragm are It is preferable that the peripheral portion of the opening on the center side and the cylindrical portion of the cap are bonded to each other with an adhesive. Further, it is preferable that the cylindrical portion of the cap functions as a heat insulating material for preventing heat transmission from the bobbin to the diaphragm.
[0013]
Another main invention of the present application is
In a speaker in which a bobbin around which a voice coil is wound is joined to a peripheral portion of an opening on the center side of the diaphragm,
A peripheral portion on the center side of a damper that supports the center side of the diaphragm between an outer peripheral portion of the bobbin and a peripheral portion of an opening on the center side of the diaphragm; and an outer peripheral edge of a cap that closes the bobbin opening. The present invention relates to a speaker characterized in that a speaker is interposed.
[0014]
Here, the cylindrical portion on the center side of the damper and the cylindrical portion on the outer peripheral side of the cap are interposed between the bobbin and the peripheral portion of the opening on the central side of the diaphragm, and the bobbin and the It is preferable that the peripheral portion of the opening on the center side of the diaphragm, the tubular portion of the damper, and the tubular portion of the cap are bonded to each other with an adhesive. Further, a cylindrical portion of the damper is adhered to an outer peripheral portion of the bobbin, a cylindrical portion of the cap is adhered to an outer peripheral portion of the cylindrical portion of the damper, and the diaphragm is attached to an outer peripheral portion of the cylindrical portion of the cap. It is preferable that the peripheral portion of the opening on the center side of is bonded.
[0015]
In a preferred aspect of the invention included in the present application, the neck portion of the heat-resistant damper is formed to be long in the axial direction between the diaphragm formed of the cone and the outer peripheral surface of the bobbin of the voice coil to form a cylindrical portion. The tubular portion is made of a heat insulating material, and the tubular portion prevents heat transfer from the bobbin around which the voice coil is wound to the diaphragm. According to such a configuration, it has been confirmed that deformation of the center part of the diaphragm and dropping from the bobbin are prevented even when a current of such a large input that the voice coil wound on the bobbin is broken is applied. I have.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS. FIGS. 1 and 2 show the overall configuration of a speaker constituting a subwoofer according to this embodiment. This speaker is provided with a frame 10 made of a substantially cup-shaped iron plate as shown in FIG. A plate 11 is attached to the lower end of the frame 10, and a ring-shaped magnet 12 is attached to the lower surface of the plate 11. A yoke 13 is fixed below the magnet 12. The yoke 13 has a center core 14 protruding upward at the center thereof. The center core 14 passes through the circular opening at the center of the plate 11, and the yoke 13 extends between the outer periphery of the center core 14 and the circular opening of the plate 11. An air gap is formed between them.
[0017]
A bobbin 15 is arranged in an air gap formed by the circular hole of the plate 11 and the center core 14, and a voice coil 16 is wound around an outer peripheral surface of the bobbin 15. Therefore, the voice coil 16 is located in the air gap of the magnetic circuit including the magnet 12, the yoke 13, the center core 14, and the plate 11. When an audio current is passed through the bobbin 15, the voice coil 16 is driven by Fleming's left-hand rule. The bobbin 15 provided with the center core 14 receives the axial force of the center core 14.
[0018]
A cone-shaped diaphragm 20 is connected to the upper end of the bobbin 15. The lower part of the diaphragm 20 is connected to the frame 10 via a damper 21. The bobbin 15 having the diaphragm 20 adhered to the outer peripheral surface is covered by a cap 22 at the opening. The outer peripheral portion of the diaphragm 20 is fixed to the outer peripheral portion of the frame 10 via a surround edge 23 whose section is curved in an arc shape.
[0019]
A decorative ring 26 is attached to the upper portion of the outer peripheral edge of the frame 10 in order to press the outer peripheral portion of the surround edge 23 and fix it to the frame 10. The decorative ring 26 is made of, for example, a molded body of a synthetic resin, and has a concave groove 27 formed on the front side thereof along the circumferential direction as shown in FIG.
[0020]
In the above configuration, the audio current supplied from the amplifier is transmitted to the voice coil 16 fitted on the bobbin 15 via the terminal 28. Therefore, such a voice coil 16 causes the diaphragm 20 to vibrate in the axial direction via the bobbin 15 according to the audio current. This causes the speaker to reproduce sound.
[0021]
In the speaker that reproduces sound in this manner, a coupling structure between the bobbin 15 and the diaphragm 20 will be described with reference to FIGS. The diaphragm 20 is a member having a cone shape that enters the inside of the frame 10, and has a circular opening 31 having substantially the same size as the bobbin 15 on the center side. A peripheral portion 32 of the opening 31 is fitted to the outer peripheral surface of the bobbin 15. A damper 21 and an auxiliary damper 24 (see FIG. 2) are used to support the diaphragm 20 and the bobbin 15 on the frame 10 so as to be movable in the axial direction.
[0022]
The diaphragm 20 is formed by vacuum forming or pressure forming a circularly punched polypropylene sheet into a cone shape. On the other hand, the bobbin 15 is made of, for example, aluminum or brass, and has a voice coil 16 wound around its outer peripheral surface. In particular, when the bobbin 15 is made of aluminum or brass, the frequency characteristics can be optimized by appropriate mass, and the heat generated by the voice coil 16 can be easily dissipated.
[0023]
On the other hand, the damper 21 has a substantially disk shape and a large number of bellows formed concentrically. The damper 21 is formed by impregnating, for example, aramid fiber or cotton cloth with a phenol resin, and forming concentric bellows-like irregularities by hot pressing.
[0024]
Next, a connection structure of the vibration plate 20, the bobbin 15, and the damper 21 will be described with reference to FIG. 4A. A cylindrical portion 33 extending in the axial direction is continuously provided on the periphery of the center hole of the damper 21. Then, the cylindrical portion 33 is fitted to the outer peripheral surface of the bobbin 15. Then, the peripheral portion 32 of the opening 31 of the diaphragm 20 is fitted on the outer peripheral surface of the cylindrical portion 33 of the damper 21, and the diaphragm 20 and the damper 21 are connected and fixed on the outer peripheral surface of the bobbin 15 by an adhesive 34. I do. The opening on the upper end side of the bobbin 15 is closed independently by the cap 22. As the adhesive 34, for example, a hard rock (trade name) is used.
[0025]
As described above, in the speaker of the present embodiment, the heat insulating tubular portion 33 of the damper 21 is interposed between the diaphragm 20 and the outer peripheral surface of the bobbin 15 around which the voice coil 16 is wound. The cylindrical portion 33 is made of a heat insulating material so as to prevent the transmission of heat from the bobbin 15 to the diaphragm 20. Therefore, even if a large current flows through the voice coil 16 on the bobbin 15 and the coil 16 generates heat, the transfer of heat from the bobbin 15 to the diaphragm 20 is blocked by the cylindrical portion 33 of the damper 21.
[0026]
FIG. 5A shows a change in temperature of the voice coil 16 and the diaphragm 20 with respect to time when an electric current is passed through the voice coil 16 on the bobbin 15 as shown in FIG. 5A. Here, even if the current at which the temperature of the voice coil 16 reaches 280 ° C. is passed through the voice coil 16, the temperature of the diaphragm 20 rises only up to about 120 to 130 ° C., so that the adhesive 34 softens and the diaphragm It was confirmed that 20 did not fall off from the bonded portion by the adhesive 34.
[0027]
According to the conventional structure, as shown in FIG. 5B, when a current at which the temperature of the voice coil reaches 280 ° C. is passed through the voice coil, when the temperature at the center of the diaphragm 2 exceeds 150 ° C. May be melted or may be separated from the bonding portion by the adhesive 5. In some cases, a disconnection accident may occur. These disadvantages are eliminated in the speaker having the structure shown in FIG. 4A by the heat insulation effect of the tubular portion 33 of the damper 21.
[0028]
FIG. 4B shows a modification. In this modification, a heat insulating effect is obtained by the cylindrical portion 33 of the cap 22 together with the cylindrical portion 33 of the damper 21. That is, the cylindrical portion 33 on the center side of the damper 21 is fitted to the outer peripheral surface of the bobbin 15. Then, a cylindrical portion 36 is formed on the outer peripheral portion of the cap 22, and this cylindrical portion 36 is fitted to the outer peripheral portion of the cylindrical portion 33 of the damper 21. Then, the peripheral portion 32 of the opening 31 of the diaphragm 20 is fitted on the outer peripheral surface of the cylindrical portion 36 of the cap 22. In such a state, the tubular portion 33 of the damper 21, the tubular portion 36 of the cap 22, and the peripheral portion 32 of the opening 31 of the diaphragm 20 are bonded and fixed on the outer peripheral surface of the bobbin 15 with a common adhesive 34.
[0029]
According to such a configuration, since the tubular portion 33 of the damper 21 and the tubular portion 36 of the cap 22 are double insulated, the transmission of heat from the bobbin 15 to the diaphragm 20 is more reliably prevented. In addition, since the cap 22 can be bonded and fixed in common with the bonding of the diaphragm 20, the number of bonding steps is reduced by one, and the workability of assembly is improved.
[0030]
FIG. 4C shows another embodiment. This embodiment is a further modification of the embodiment shown in FIG. 4B. That is, the lower end side of the cylindrical portion 36 on the outer peripheral side of the cap 22 is lengthened so that the portion of the peripheral portion 32 of the opening 31 of the diaphragm 20 is covered by the cylindrical portion 36. Therefore, the heat insulating effect of the cylindrical portion 36 of the cap 22 becomes more complete.
[0031]
FIG. 4D shows still another embodiment. In this embodiment, the cylindrical portion 33 of the damper 21 is fitted to the outer peripheral surface of the bobbin 15, and the peripheral portion 32 of the opening 31 of the diaphragm 20 is brought into contact with the outer peripheral surface of the cylindrical portion 33 of the damper 21; In addition, the tubular portion 36 of the cap 22 is inserted into a V-shaped portion formed between the outer peripheral surface of the tubular portion 33 and the peripheral portion 32 of the opening 31 of the diaphragm 20. Is bent outward and the bent portion is joined to the upper surface of the diaphragm 20. Here, the cylindrical portion 33 of the damper 21, the peripheral portion 32 of the opening 31 of the diaphragm 20, and the cylindrical portion 36 of the cap 22 are bonded and fixed with a common adhesive 34. Such a configuration has the effect of increasing the heat insulating property by the cylindrical portion 36 of the cap 22 and increasing the bonding area of the diaphragm 22 particularly by increasing the bonding area of the cap 22.
[0032]
FIG. 4E shows another modification. In this modification, the cylindrical portion 36 of the cap 22 is directly fitted on the outer peripheral surface of the bobbin 15, and the cylindrical portion 33 of the damper 21 is fitted on the outer peripheral surface of the cylindrical portion 36 of the cap 22. The outer peripheral surface of the cylindrical portion 33 of the damper 21 is fitted with the peripheral edge portion 32 of the opening 31 of the diaphragm 20 and is bonded and fixed with a common adhesive 34. Therefore, even with such a configuration, the tubular portion 36 of the cap 22 and the tubular portion 33 of the damper 21 provide double heat insulation, thereby preventing the transfer of heat from the bobbin 15 to the diaphragm 20. Further, since the tubular portion 36 of the cap 22 is sandwiched between the bobbin 15 and the tubular portion 33 of the damper 21, there is an advantage that the joining strength of the cap 22 is enhanced.
[0033]
The invention included in the present application has been described above with reference to the illustrated embodiment. However, the invention included in the present application is not limited to the above embodiment, and various modifications may be made within the technical idea of the invention included in the present application. Is possible. For example, the above embodiment relates to a subwoofer, but the present invention can be widely applied to speakers that cover various other sound ranges. Also, the materials of the bobbin 15, the diaphragm 20, and the damper 21 are not limited by the above embodiment, and various materials can be arbitrarily selected.
[0034]
【The invention's effect】
The main invention of the present application is a speaker in which a bobbin around which a voice coil is wound is joined to a peripheral portion of an opening on the center side of a diaphragm, between a peripheral portion of the bobbin and a peripheral portion of an opening on the center side of the diaphragm. In this case, a peripheral portion on the center side of a damper that supports the center side of the diaphragm is interposed.
[0035]
Therefore, according to such a configuration, heat transfer from the bobbin to the diaphragm is prevented by the peripheral portion on the central side of the damper interposed between the bobbin and the peripheral portion of the opening on the central side of the diaphragm.
[0036]
Another main invention is a speaker in which a bobbin around which a voice coil is wound is joined to a peripheral portion of an opening on a center side of a diaphragm, wherein a speaker is provided between an outer peripheral portion of the bobbin and a peripheral portion of an opening on a center side of the diaphragm. The outer periphery of the cap that closes the opening of the bobbin is interposed.
[0037]
Therefore, according to such a speaker, the transfer of heat from the bobbin to the diaphragm is prevented by the outer peripheral edge of the cap.
[0038]
Still another main invention of the present application is a speaker in which a bobbin around which a voice coil is wound is joined to a peripheral portion of an opening on a center side of a diaphragm, wherein an outer peripheral portion of the bobbin and a peripheral portion of an opening on a center side of the diaphragm are provided. A peripheral portion of the center of the damper that supports the center of the diaphragm and an outer peripheral edge of the cap that closes the opening of the bobbin are interposed therebetween.
[0039]
Therefore, according to such a loudspeaker, the bobbin moves from the bobbin to the diaphragm by the peripheral portion on the center side of the damper and the peripheral edge of the cap interposed between the outer peripheral portion of the bobbin and the peripheral portion of the opening on the central side of the diaphragm. Is prevented from transmitting.
[Brief description of the drawings]
FIG. 1 is a front view of a speaker.
FIG. 2 is a sectional view of the speaker taken along line AA in FIG. 1;
FIG. 3 is an exploded perspective view showing a coupling structure of a diaphragm, a damper, and a bobbin.
FIG. 4 is a longitudinal sectional view of an essential part showing a coupling structure of a bobbin, a diaphragm and a damper.
FIG. 5 is a graph showing a change in the temperature at the center of the diaphragm as the temperature of the voice coil rises.
FIG. 6 is an enlarged sectional view of a main part showing a coupling structure of a bobbin, a diaphragm and a damper of a conventional speaker.
[Explanation of symbols]
1 bobbin, 2 diaphragm, 3 opening edge, 4 damper, 5 adhesive, 10 frame, 11 plate, 12 magnet, 13 yoke, 14 ‥‥ Center core, 15 ‥‥ bobbin, 16 ‥‥ voice coil, 20 ‥‥ diaphragm, 21 ‥‥ damper, 22 ‥‥ cap, 23 ‥‥ surround edge, 24 ‥‥ auxiliary damper, 26 ‥‥ decorative ring, 27 {Concave groove, 28} Terminal, 31} Opening, 32% Opening Peripheral Edge, 33 ° Cylindrical Part (Damper), 34 ° Adhesive, 36 ° Cylindrical Part (Cap)

Claims (10)

In a speaker in which a bobbin around which a voice coil is wound is joined to a peripheral portion of an opening on the center side of the diaphragm,
A loudspeaker characterized in that a peripheral part on the center side of a damper supporting a central side of the diaphragm is interposed between an outer peripheral part of the bobbin and a peripheral part of an opening on the central side of the diaphragm. A cylindrical portion is continuously provided on a peripheral portion on the center side of the damper, and the cylindrical portion is interposed between the bobbin and a peripheral portion of an opening on the center side of the diaphragm, and the bobbin and the vibration The speaker according to claim 1, wherein a peripheral portion of the opening on the center side of the plate and a cylindrical portion of the damper are bonded to each other with an adhesive. The loudspeaker according to claim 2, wherein the tubular portion of the damper functions as a heat insulating material for preventing transmission of heat from the bobbin to the diaphragm. 3. The speaker according to claim 2, wherein an outer peripheral edge of a cap that closes an opening of the bobbin is adhered so as to extend over a cylindrical portion of the damper and a peripheral edge of an opening on a center side of the diaphragm. 4. In a speaker in which a bobbin around which a voice coil is wound is joined to a peripheral portion of an opening on the center side of the diaphragm,
A speaker, wherein an outer peripheral edge of a cap for closing the bobbin opening is interposed between an outer peripheral portion of the bobbin and a peripheral portion of an opening on a center side of the diaphragm. A cylindrical portion is continuously provided on an outer peripheral edge of the cap, and the cylindrical portion is interposed between the bobbin and a peripheral portion of an opening on a center side of the diaphragm. The loudspeaker according to claim 5, wherein the peripheral portion of the opening on the side and the tubular portion of the cap are adhered to each other with an adhesive. The loudspeaker according to claim 6, wherein the tubular portion of the cap functions as a heat insulating material for preventing transmission of heat from the bobbin to the diaphragm. In a speaker in which a bobbin around which a voice coil is wound is joined to a peripheral portion of an opening on the center side of the diaphragm,
A peripheral portion on the center side of a damper that supports the center side of the diaphragm between an outer peripheral portion of the bobbin and a peripheral portion of an opening on the center side of the diaphragm; and an outer peripheral edge of a cap that closes the bobbin opening. A speaker, wherein a speaker is interposed. A cylindrical portion on the center side of the damper and a cylindrical portion on the outer peripheral side of the cap are interposed between the bobbin and a peripheral portion of a central opening of the diaphragm, and the bobbin and the diaphragm 9. The loudspeaker according to claim 8, wherein the peripheral portion of the opening on the center side of the boss, the tubular portion of the damper, and the tubular portion of the cap are bonded to each other with an adhesive. The cylindrical portion of the damper is bonded to the outer peripheral portion of the bobbin, the cylindrical portion of the cap is bonded to the outer peripheral portion of the cylindrical portion of the damper, and the diaphragm of the diaphragm is mounted to the outer peripheral portion of the cylindrical portion of the cap. The speaker according to claim 9, wherein a peripheral portion of the opening on the center side is bonded.

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