JPH0795692A - Dome speaker - Google Patents

Abstract

PURPOSE:To provide a dome speaker of wide band capable of effectively preventing the occurrence of an eddy current in a coil bobbin. CONSTITUTION:The dome speaker outputs a sound generated based on the vibration of a metallic dome shape diaphragm 10. In the dome speaker, the coil bobbin 11 around which a voice coil 12 is wound is formed integrally with the dome shape dialphragm 10, and also, plural slits 11a in a direction intersecting orthogonally to the winding direction of the voice coil 12 are formed keeping a prescribed gap.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dome speaker using a dome-shaped diaphragm suitable for application to a horn speaker.

[0002]

2. Description of the Related Art A dome-shaped diaphragm made of metal is used as a diaphragm in a horn speaker or the like for reproducing sounds in a high range. For example, in the case of a horn speaker,
After the sound output from the dome-shaped diaphragm is collected via a phase equalizer called an equalizer, the collected sound from the diaphragm is guided to the horn, and the sound is output from the horn. It is configured to output to.

In this case, a voice coil wound around a coil bobbin connected to a diaphragm is arranged at a position where magnetic force acts by a magnetic circuit of a speaker, and a dome shape is formed based on a voice signal supplied to the voice coil. The diaphragm vibrates and a predetermined sound is output.

[0004]

By the way, in the case of a speaker using such a metal dome-shaped diaphragm, the coil bobbin around which the voice coil is wound is also made of metal. There is a problem that eddy current is likely to be generated in the coil bobbin due to the vibration of the linked voice coil. When such an eddy current is generated, a reverse braking force is applied to the vibration plate, which makes it difficult to reproduce the middle and low frequencies.

In the case of a metal dome with a bobbin integrated,
Since the mechanical Q of the vibration system is high, there is a drawback that a peak is likely to occur in the high frequency range.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a broadband dome speaker which can effectively prevent the generation of eddy currents in the coil bobbin.

[0007]

The present invention is described in, for example, FIG.
As shown in FIG. 3, in a dome speaker that outputs a sound generated based on vibration of a metal dome-shaped diaphragm 10, a coil bobbin 11 that winds a voice coil 12 around the dome-shaped diaphragm 10 is integrated. In addition to the above, the coil bobbin 11 is formed with a plurality of slits 11a in a direction orthogonal to the winding direction of the voice coil 12 at predetermined intervals.

[0008]

According to the present invention, the coil bobbin 11 is formed by the slits 11a formed at predetermined intervals in the coil bobbin 11.
The generation of eddy currents in the interior is prevented, there is no influence of eddy currents, etc., and it is possible to obtain a speaker with good frequency characteristics with few peaks.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

The speaker of this example has a frequency of several hundred Hz (for example, 500 Hz).
It is configured as a horn speaker used in a frequency band higher than (Hz) and is configured as shown in FIG. In addition, FIG. 2 is an exploded view of the main part. In FIG. 1, reference numeral 10 denotes a diaphragm. The diaphragm 10 is formed of a metal plate such as aluminum in a dome shape, and a cylindrical coil bobbin 11 is formed on an outer peripheral portion of a dome-shaped curved portion. A voice coil 12 is wound around. And
As shown in FIG. 3, the coil bobbin 11 of the present example has a plurality of slits 11a formed at predetermined intervals in a direction orthogonal to the direction in which the voice coil 12 is wound (that is, the direction in which the voice coil 12 moves during vibration). The diaphragm 10 shown in FIG. 2 and FIG.
Indicates a state in which the voice coil 12 is not wound around the coil bobbin 11.

An edge 1 is formed on the outer peripheral portion of the diaphragm 10.
3 are connected, and the edge 13 is sandwiched between the speaker unit side plate 21 and the annular restraining member 24 arranged on the plate 21, so that the diaphragm 10
Are supported on the speaker unit side. In this case, spacers 22 and 23 are arranged between the plate 21 and the restraining member 24 as needed to adjust the mounting height of the diaphragm 10. Then, using the screw 25a,
The holding member 24 is fixed to the plate 21, and the edge 13 of the diaphragm 10 is fixed to the speaker unit side. Also,
Use the screw 25b from the side opposite to this screw 25a,
The guide ring 26 is simultaneously fixed to the lower part of the plate 21. The guide ring 26 has a shape in which the step portion 26a is fitted in the step portion 21a on the plate 21 side, and the guide ring 26 is set with the mounting position of the plate 21 as a reference.
The mounting position of is determined.

Then, the equalizer 30 is arranged along the curved shape of the diaphragm 10 curved in a dome shape. The equalizer 30 acts as a phase equalizer that collects and outputs the sound generated by the vibration of the diaphragm 10 in phase with each other. The equalizer 30 is formed by aluminum die casting and has four concentric circular slits. 31, 32, 33, 34
Is formed, the sound from the diaphragm 10 is generated by the slit 3
1-34.

Then, a cylindrical pole piece 27 is attached to the side of the equalizer 30 opposite to the diaphragm 10 (lower side in FIG. 1). Outer circumference 27a of this pole piece 27
Has the same diameter as the inner circumference 26a of the guide ring 26, and the inner circumference 26a of the guide ring 26 and the pole piece 27
The pole piece 27 is attached so as to be in contact with the outer periphery 27a. Therefore, the guide ring 26
The mounting position of the pole piece 27 is determined with reference to the mounting position of. Further, a through hole 27b for connecting a throat 29, which will be described later, is formed in the center of the pole piece 27.
Are formed. The pole piece 27 is a component that constitutes the magnetic circuit of the speaker together with the above-described plate 21 and the like, and is made of a magnetic material.

On the surface where the pole piece 27 and the equalizer 30 are in contact with each other, the protrusion 35 on the equalizer 30 side is provided.
A recess 27c that fits in the pole piece 27 is formed in the pole piece 27, and the projection 35 fits in the recess 27c.
0 is attached to the pole piece 27 in a slightly floating state,
A slit 36 is formed between the pole piece 27 and the equalizer 30.

Then, the equalizer 3 of the pole piece 27
On the side opposite to 0 (the lower side in FIG. 1), an annular magnet 2
You can place 8. A through hole 28a for connecting a throat 29, which will be described later, is also formed in the central portion of the magnet 28. The through hole 28a has a diameter slightly larger than the through hole 27b of the pole piece 27 described above. There is.

The through hole 28 at the center of the magnet 28
A cylindrical throat 29 is arranged in a and the through hole 27b at the center of the pole piece 27. This throat 29
Is a member for transmitting the sound output from the equalizer 30 to the horn side, and is a through hole 29 for passing the sound.
a. The diameter of the through hole 29a gradually increases as it goes away from the portion near the equalizer 30. The outer periphery 29b of the throat 29 is the magnet 2
8 is fitted in the through hole 28a and the outer circumference 2
The tip 29c of 9b has a slightly smaller diameter, and the tip 29c having the smaller diameter is shaped to fit into the through hole 27b of the pole piece 27. Therefore, the position of the throat 29 is determined based on the through hole 27b of the pole piece 27, and the position of the magnet 28 is determined based on the position of the throat 29. In this example, the throat 29 is made of copper. 1. Then, the yoke 41 having a circular through hole 41a into which the outer periphery 29b of the throat 29 is fitted is attached in a state of being fitted into the throat 29. The yoke 41 includes the guide ring 26,
The pole piece 27 and the magnet 28 are shaped so as to cover the outer peripheral portions thereof and come into contact with the plate 21. The yoke 41 is made of a magnetic material and has a screw hole 41b for mounting a horn (not shown). Then, on the surface (upper surface in FIG. 1) opposite to the yoke 41 of this speaker unit,
Attach the back cover 42. This back cover 42
Is attached to the yoke 41 side via the plate 21 by screwing or the like.

With this configuration, the pole piece 27, the magnet 28, and the voice coil 1 arranged on the inner peripheral side of the voice coil 12 attached to the diaphragm 10 are provided.
The plate 21 arranged on the outer peripheral side of 2 and the yoke 41 connecting the magnet 28 and the plate 21 constitute a magnetic circuit as a speaker, and the diaphragm 10 is based on the drive signal supplied to the voice coil 12. Vibrates, and a sound based on the drive signal is output.

Here, the throat 29 from the equalizer 30.
2, the plate 21 and the guide ring 26 have screw holes 21b and 26d, respectively.
It is fixed with screws using the pole piece 27
The magnet 28 is fixed to the pole piece 2 by the magnet 28.
It is fixed by the magnetic force by the magnetization of 7. In addition, although the yoke 41 is not shown in FIG. 2, the yoke 41 and the magnet 28 are also fixed by magnetic force by magnetizing the yoke 41 by the magnet 28. The diaphragm 10 shown in FIG. 2 shows a state in which no edge is attached.

According to the speaker thus constructed,
The coil bobbin 11 integrated with the diaphragm 10 has slits 11a formed at predetermined intervals.
And the frequency characteristics of the speaker become good. That is, even if the voice coil 12 is vibrated in conjunction with the diaphragm 10, the action of the slits 11a formed at predetermined intervals in the coil bobbin 11 prevents the generation of an eddy current in the metallic coil bobbin 11. . Further, the mechanical Q of the dome portion is lowered by the effect of the slit 11a. Therefore, it is possible to obtain a dome speaker that is not affected by eddy currents and has good frequency characteristics with few high-frequency peaks.

FIG. 4 shows a frequency characteristic f ₁ of a dome speaker using the diaphragm 10 of this embodiment in which the slit 11a is formed in the coil bobbin 11 and a dome speaker using a conventional diaphragm without slits in the coil bobbin. Frequency characteristics f ₂ of As can be seen from FIG. 4, the frequency characteristic f ₁ of the diaphragm 10 of this example has a higher level in the low range of 1 kHz or less and a higher frequency of 10 kHz or more than the characteristic f ₂ without the slit. The frequency characteristics in the range are flatter than those without slits, and the characteristics are good.

In the above-described embodiment, the example in which the equalizer is applied to the horn speaker in which the equalizer is arranged close to the dome-shaped diaphragm 10 has been described. Of course, the present invention can be applied to a normal dome speaker that emits sound, and the same frequency characteristic improvement effect can be obtained in this case as well.

[0022]

According to the present invention, the slits formed at predetermined intervals in the coil bobbin prevent the generation of eddy currents in the coil bobbin, lower the mechanical Q of the diaphragm, and reduce the influence of eddy currents. Therefore, it is possible to obtain a dome speaker having good frequency characteristics with few high-frequency peaks.

[Brief description of drawings]

FIG. 1 is a sectional view showing a speaker of an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a main part of the speaker according to the embodiment.

FIG. 3 is a perspective view showing a diaphragm applied to the speaker of the present invention.

FIG. 4 is a frequency characteristic diagram for explaining one embodiment.

[Explanation of symbols]

 10 Vibrating Plate 10a Dome Part 11 Coil Bobbin 11a Slit 12 Voice Coil 21 Plate 26 Guide Ring 27 Pole Piece 28 Magnet 29 Throat 30 Equalizer 31, 32, 33, 34 Slit

Claims (1)

[Claims] 1. A dome speaker for outputting a sound generated based on vibration of a metallic dome-shaped diaphragm, wherein a coil bobbin for winding a voice coil is integrally formed on the dome-shaped diaphragm, and A dome speaker, wherein a plurality of slits in a direction orthogonal to a winding direction of the voice coil are formed at predetermined intervals on the coil bobbin.