JP2000308185A - Loudspeaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tweeter with enlarged magnetic force in a magnetic cavity even with the magnet of comparatively small magnetic force. SOLUTION: This speaker has a U-shaped yoke 10 of a prescribed length with which one side wall 10a is lower than another side wall 10b, a center plate 13 arranged between one and the other side walls and held between first and second magnets 11 and 12, a first plate 14 for forming a slender first magnetic cavity 15 between the other end face and the side face of the center plate while fixing one end to the upper end of one side wall of the U-shaped yoke, a second plate 16 provided parallel with the other side wall on the other end, a third plate 17 for forming a slender second magnetic cavity 18 between the other end face and the upper end of the other side wall while fixing one end to the upper end of the other side wall of the U-shaped yoke and a diaphragm 20 equipped with a plane voice coil 21 around the first and second magnetic cavities while fixing one end side through a gasket 22 onto the third plate and inserting the other end side to the said first and second magnetic cavities.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to, for example, 100 kHz.
The present invention relates to a loudspeaker for high sounds that can be reproduced up to an extremely high frequency range up to z.

[0002]

2. Description of the Related Art FIG.
Also, a ribbon-shaped speaker as shown in FIG. 9 has been proposed.

Referring to the ribbon-shaped speaker shown in FIGS. 8 and 9, reference numeral 1 denotes a rectangular magnet, and a plate-shaped yoke 2a having a predetermined shape is provided in contact with the N pole of the rectangular magnet 1. A plate yoke 2b having the same shape as the plate yoke 2a is provided in contact with the S pole of the magnet 1.

One end of each of the rectangular plates 3a and 3b is fixed to the upper end surface of each of the plate-like yokes 2a and 2b, and a relatively wide predetermined length is provided between the other end surfaces of the plates 3a and 3b. Is formed.

A ribbon-shaped diaphragm 5 made of a conductive material, for example, an aluminum thin plate, is inserted into the magnetic gap 4, and one end of the ribbon-shaped diaphragm 5 is insulated and held at one end of the magnetic gap 4 by a holding member 6a. At the same time, it is connected to one input terminal 7a, the other end of the ribbon-shaped diaphragm 5 is insulated and held by the holding member 6b at the other end of the magnetic gap 4, and is connected to the other input terminal 7b.

The audio signal supplied to the audio signal input terminals 8a and 8b is supplied to one and the other input terminals 7a and 7b via a transformer (matching transformer) 9 for impedance conversion. In this case, since the impedance of the ribbon-shaped diaphragm 5 is extremely small, the matching transformer 9 is provided.

In the ribbon-shaped speaker shown in FIGS. 8 and 9, one and the other input terminals 7a and 7
When a current flows through the ribbon-shaped diaphragm 5 in accordance with the acoustic signal supplied between b and b, the diaphragm 5 vibrates according to the framing left-hand rule to emit high-pitched sounds.

[0008]

However, in the ribbon-shaped speaker as shown in FIGS. 8 and 9, the width of the magnetic gap 4 necessary for moving the ribbon-shaped diaphragm 5 is very large. 4, in order to generate a large magnetic force, the magnet 1 having a very large magnetic force is required, and the magnet 1 having such a large magnetic force is disadvantageous in that it is difficult and expensive to manufacture. Was.

In view of the above, the present invention proposes a loudspeaker for a high-pitched sound in which a magnet having a relatively small magnetic force can increase the magnetic force in a magnetic gap.

[0010]

According to the present invention, there is provided a loudspeaker comprising: a U-shaped yoke having a predetermined length with one side wall being lower than the other side wall;
A center plate disposed between one and the other side walls of the U-shaped yoke and sandwiched between the first and second magnets; one end fixed to the upper end of one side wall of the U-shaped yoke; A first plate disposed so as to form an elongated first magnetic gap between the side surface of the center plate and a second plate provided on the other end of the first plate in parallel with the other side wall; And a third plate fixed at one end to the upper end of the other side wall of the U-shaped yoke and arranged so as to form an elongated second magnetic gap between the other end surface and the side surface of the second plate. , One end is fixed on the third plate via a gasket, and the other end is inserted into the first and second magnetic gaps and a planar voice is formed so as to surround the first and second magnetic gaps. Vibration with coil And it has a door.

According to the present invention, the elongated first and second elongated members are provided.
Since only the planar voice coil provided on the thin diaphragm is inserted into the magnetic gap, the gap width of the first and second magnetic gaps can be made very small, and the magnet has a relatively small magnetic force. Also, the magnetic force of the first and second magnetic air gaps can be greatly increased.

Also, the speaker of the present invention is provided with a U-shaped yoke having one side wall lower than the other side wall and a predetermined length between the first and second side walls of the U-shaped yoke.
A center plate sandwiched between the magnets, and one end is fixed to an upper end of one side wall of the U-shaped yoke, and is arranged so as to form an elongated first magnetic gap between the other end surface and a side surface of the center plate. The first plate,
A second plate provided on the other end of the first plate in parallel with the other side wall; one end fixed to the upper end of the other side wall of the U-shaped yoke; A third plate disposed so as to form an elongated second magnetic gap between the first plate and the side surface of the third plate, one end of which is fixed on the third plate via a gasket;
And the first and second magnetic gaps and
And a drive coil wound around the outer periphery of the second plate.

According to the present invention, the first and second elongated members are provided.
Since only the flat short coil provided on the thin diaphragm is inserted into the magnetic gap, the gap width of the first and second magnetic gaps can be made very large, and the magnet has a relatively small magnetic force. Also, the magnetic force of the first and second magnetic air gaps can be greatly increased.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the speaker of the present invention will be described below with reference to FIGS. 1, 2, 3 and 4. FIG.

1, 2 and 4, reference numeral 10 denotes a U-shaped yoke in which one side wall 10a is lower than the other side wall 10b by a predetermined length, and between the one and other side walls 10a and 10b of the U-shaped yoke 10. Is provided with a rectangular center plate 13 of a predetermined size sandwiched between two ring-shaped magnets 11 and 12 made of, for example, ferrite magnets and having a predetermined thickness.

In this case, the N-pole surface of the ring-shaped magnet 11 is bonded and fixed to the inner surface of one side wall 10a of the U-shaped yoke 10, and one side surface of the center plate 13 is attached to the S-pole surface of the ring-shaped magnet 11. Glued and fixed,
The S pole surface of the ring-shaped magnet 12 is bonded and fixed to the other side surface of the center plate 13, and the inner surface of the other side surface 10 b of the U-shaped yoke 10 is bonded and fixed to the N pole surface of the ring magnet 12.

One side wall 10a of the U-shaped yoke 10
One end of a rectangular plate 14 is adhesively fixed to the upper end of the
An elongated magnetic air gap 15 is formed between the upper end portion and one side surface.

On the other end of the plate 14, a predetermined rectangular plate 16 is placed on the other side wall 10 of the U-shaped yoke 10.
One end face is bonded and fixed so as to be parallel to b.

In this embodiment, a rectangular plate 17 is provided on the upper end of the other side wall 10b of the U-shaped yoke 10.
And an elongated magnetic gap 18 is formed between the other end surface of the plate 17 and the side surface of the upper end of the plate 16.

In this case, the elongated magnetic gaps 15 and 1
The gap width of 8 is extremely narrow for inserting a planar voice coil 21 made of, for example, an aluminum thin plate provided integrally with a diaphragm 20 described later. In this case, the magnetic air gap 1
The magnetic forces of 5 and 18 are applied to the magnets 11 and 12 respectively.
Even if the magnetic force is relatively small, it can be extremely large.

In this embodiment, one side edge 20 of a diaphragm 20 made of a predetermined rectangular, for example, synthetic resin thin plate is used.
a is adhered and fixed on the plate 17 via the gasket 22, the vibrating plate 20 is formed into a dome shape, and the other side facing the edge portion 20a is provided with the magnetic gaps 18 and 15.
So that it can be inserted into

In this case, in this example, this diaphragm 20
A one-turn planar voice coil 21 is formed around (along) the magnetic air gaps 15 and 18 by, for example, an aluminum thin plate.
Is provided integrally with the diaphragm 20.

As an example of the diaphragm 20, as shown in FIG. 3, for example, an edge portion 20a on one side of a rectangular thin plate made of a synthetic resin is linearly adhered and fixed to a gasket 22, and the diaphragm 20 is formed in a dome shape. , This edge portion 20
A one-turn planar voice coil 21 is integrally provided on the other side opposite to a by, for example, an aluminum thin plate so as to surround (along) the magnetic gaps 15 and 18.

In this case, when the diaphragm 20 is formed of a synthetic resin, the aluminum thin plate forming the planar one-turn voice coil 21 may be integrally formed with the diaphragm by aluminum insert technology. I do.

Input terminals 23a and 23b are provided at both ends of the planar voice coil 21, respectively. In this embodiment, the input terminals 23a are connected to an audio signal input terminal 24a provided at a predetermined position on the plate 14 and input. Terminal 23
b is connected to an audio signal input terminal 24b provided at a predetermined position on the other side wall 10b of the U-shaped yoke 10, and an audio signal is supplied to the input terminals 23a and 23b.

In order to hold the planar one-turn voice coil 21 integrally provided on the diaphragm 20 in the elongated magnetic gaps 15 and 18, respectively, the magnetic gaps 15 and 18 are used.
A magnetic fluid 25 having viscosity in a magnetic field is injected into the inside.

Since the present embodiment is constructed as described above, the magnetic circuit according to the present embodiment is arranged such that the magnetic flux from the N pole of the ring magnet 11 is equal to the N of the ring magnet 11 as shown in FIG.
Pole → one side wall 10a of U-shaped yoke 10 → plate 1
4 → magnetic gap 15 → center plate 13 → magnetic circuit of S-pole of ring-shaped magnet 11 and N-pole of ring-shaped magnet 11 → one side wall 10a of U-shaped yoke 10 → bottom → other side wall 10b → plate 17 → Magnetic gap 18 →
Plate 16 → Magnetic gap 15 → Center plate 13 →
It flows through the magnetic circuit of the S pole of the ring-shaped magnet 11.

The magnetic flux from the N-pole of the ring-shaped magnet 12 is transferred to the N-pole of the ring-shaped magnet 12 → the other side wall 10 b of the U-shaped yoke 10 → the plate 17 → the magnetic air gap 1.
8 → Plate 16 → Magnetic gap 15 → Center plate 1
3 → S-pole magnetic circuit of ring-shaped magnet 12 and N-pole of ring-shaped magnet 12 → other side wall 10b of U-shaped yoke 10 → bottom → one side wall 10a → plate 14 →
It flows through the magnetic gap 15 → the center plate 13 → the magnetic circuit of the S pole of the ring-shaped magnet 12.

Accordingly, the input terminals 23a and 23a of the one-turn planar voice coil 21 provided integrally with the diaphragm 20 are provided.
When an audio signal is supplied between the voice coils 3b, a current corresponding to the audio signal flows through the planar voice coil 21 and the planar voice coil 2 is driven by the framing left hand rule.
1, ie, the diaphragm 20 vibrates and emits a high sound.

According to this embodiment, since the planar voice coil 21 which is, for example, an aluminum thin plate provided integrally with the diaphragm 20 is simply inserted into the elongated magnetic gaps 15 and 18, the magnetic gaps 15 and 18 are formed. Even if the magnets 11 and 12 are inexpensive and have relatively small magnetic force, the magnetic force of the magnetic air gaps 15 and 18 can be extremely large, and the cost and high sound quality can be reduced. A high-pitched speaker can be obtained.

As shown in FIG. 1, in a dynamic high-frequency loudspeaker using a one-turn planar voice coil 21, the impedance of the planar voice coil 21 is very small. Although a transformer is used, when the treble speaker and the main speaker are used in combination, the planar voice coil 21 of the treble speaker of this example is connected in series to the voice coil of the main speaker. In this case, the matching transformer can be omitted.

FIGS. 5, 6 and 7 show another embodiment of the speaker according to the present invention. 5, 6 and 7, parts corresponding to those in FIGS. 1 and 2 are denoted by the same reference numerals.

Also in this example, one side wall 10a is shorter than the other side wall 10b by a predetermined length. A rectangular center plate 13 of a predetermined size sandwiched between the magnets 11 and 12 is provided.

In this case, the N-pole surface of the ring-shaped magnet 11 is bonded and fixed to the inner surface of one of the side walls 10a of the U-shaped yoke 10, and one side surface of the center plate 13 is attached to the S-pole surface of the ring-shaped magnet 11. Glued and fixed,
The S pole surface of the ring-shaped magnet 12 is bonded and fixed to the other side surface of the center plate 13, and the inner surface of the other side wall 10 b of the U-shaped yoke 10 is bonded and fixed to the N pole surface of the ring magnet 12.

One end of a rectangular plate 14 is adhesively fixed to the upper end of one side wall 10a of the U-shaped yoke, and an elongated magnetic field is formed between the other end of the plate 14 and one side of the upper end of the center plate 13. The space 15 is formed.

On the other end of the plate 14, a predetermined rectangular plate 16 is placed on the other side wall 10 of the U-shaped yoke 10.
One end face is bonded and fixed so as to be parallel to b.

In this embodiment, a rectangular plate 17 is provided on the upper end of the other side wall 10b of the U-shaped yoke 10.
And an elongated magnetic gap 18 is formed between the other end surface of the plate 17 and the side surface of the upper end of the plate 16.

In this case, the elongated magnetic air gaps 15 and 1
The gap width of 8 is extremely small for inserting a flat short coil 31 made of, for example, an aluminum thin plate provided integrally with a diaphragm 30 described later. At this time, the magnetic forces of the magnetic gaps 15 and 18 are applied to the magnets 11 and 1 respectively.
Even if the magnetic force of No. 2 is relatively small, it can be extremely large.

In the present embodiment, one edge portion 30 of one side of the diaphragm 30 made of a predetermined rectangular, for example, thin synthetic resin plate.
a is adhered and fixed on the plate 17 via the gasket 32, the diaphragm 30 is formed into a dome shape, and the other side opposite to the edge portion 30a is provided with the magnetic gaps 18 and 15.
So that it can be inserted into

In this case, in this example, the diaphragm 30
An annular planar short coil 31 is formed around (along) the magnetic gaps 15 and 18 by, for example, an aluminum thin plate.
Is provided integrally with the diaphragm 30.

As an example of the diaphragm 30, as shown in FIG. 7, for example, an edge portion 30a on one side of a rectangular thin plate made of a synthetic resin is linearly adhered and fixed to a gasket 32, and the diaphragm 30 is formed in a dome shape. , This edge portion 30
An annular flat short coil 31 is integrally provided on the other side opposite to a so as to surround (along) the magnetic gaps 15 and 18 by, for example, an aluminum thin plate.

In this case, when the diaphragm 30 is made of synthetic resin, the flat annular short coil 3
1 can be formed integrally with the diaphragm by aluminum insert technology.

Also, in this embodiment, as shown in FIGS. 5 and 6, along the outer periphery of the plate 16, that is, below the elongated magnetic gap 15 (below the plate 14) and the magnetic gap 18
The drive coil 33 is wound along the upper side (the upper end side of the plate 16), and the drive coil 33 is bonded and fixed. In this example, an acoustic signal is supplied to the drive coil 33.

One side and the other side of the annular planar short coil 31 on the other side of the diaphragm 30 are elongated magnetic gaps 15.
And 18 in order to keep them in the magnetic air gaps 15 and 18.
A magnetic fluid 25 having viscosity in a magnetic field is injected into the inside.

Since the present embodiment is configured as described above, the magnetic circuit according to the present embodiment is, as shown in FIG.
The magnetic flux from the N-pole of the ring-shaped magnet 11 is transferred to the N-pole of the ring-shaped magnet 11 → one side wall 10a of the U-shaped yoke 10 → the plate
→ Magnetic gap 15 → Center plate 13 → S-pole magnetic circuit of ring-shaped magnet 11 and ring-shaped magnet 1
1 N pole → one side wall 10a of U-shaped yoke 10 → bottom → other side wall 10b → plate 17 → magnetic gap 18 → plate 16 → magnetic gap 15 → center plate 13 → magnetic circuit of S pole of ring-shaped magnet 11 And flowing.

The magnetic flux from the N-pole of the ring-shaped magnet 12 is transferred to the N-pole of the ring-shaped magnet 12 → the other side wall 10 b of the U-shaped yoke 10 → the plate 17 → the magnetic air gap 1.
8 → Plate 16 → Magnetic gap 15 → Center plate 1
3 → S-pole magnetic circuit of ring-shaped magnet 12 and N-pole of ring-shaped magnet 12 → other side wall 10b of U-shaped yoke 10 → bottom → one side wall 10a → plate 14 →
It flows through the magnetic gap 15 → the center plate 13 → the magnetic circuit of the S pole of the ring-shaped magnet 12.

Therefore, when an acoustic signal is supplied to the drive coil 33, a short-circuit current corresponding to the acoustic signal flows through the planar short coil 31 provided integrally with the diaphragm 30 by electromagnetic induction. 30 vibrates according to this acoustic signal, and can emit high-pitched sounds.

According to the present embodiment, the elongated magnetic air gap 15
Since only the flat short coil 31 provided integrally with the diaphragm is inserted into the magnets 18 and 18, the width of the magnetic gaps 15 and 18 can be made very small, and the magnets 11, which are inexpensive and have relatively small magnetic force. Even with 12, the magnetic force of the magnetic gaps 15 and 18 can be made extremely large, and an inexpensive and high-quality loudspeaker for high sound can be obtained.

As shown in FIG. 5, in the treble speaker of the electromagnetic induction type, since the impedance of the drive coil 33 is relatively large, no matching transformer is required.

It should be noted that the present invention is not limited to the above-described example, and may adopt various other configurations without departing from the gist of the present invention.

[0051]

According to the present invention, the width of the magnetic gap can be made very small, and even if an inexpensive magnet having a relatively small magnetic force is used, the magnetic force of this magnetic gap can be made very large. It is possible to obtain an inexpensive and high-quality loudspeaker for high sound.

[Brief description of the drawings]

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

FIG. 2 is a perspective view showing a state where a diaphragm in the example of FIG. 1 is removed.

FIG. 3 is a perspective view showing an example of the diaphragm shown in FIG. 1;

FIG. 4 is a sectional view of FIG. 2;

FIG. 5 is a perspective view showing another example of the embodiment of the speaker of the present invention.

FIG. 6 is a perspective view showing a state where a diaphragm in the example of FIG. 5 is removed.

FIG. 7 is a perspective view showing an example of the diaphragm shown in FIG. 5;

FIG. 8 is a plan view showing an example of a conventional ribbon-shaped speaker.

FIG. 9 is a sectional view of FIG. 8;

[Explanation of symbols]

10 ° U-shaped yoke, 10a One side wall, 10b
{The other side wall, 11, 12} Magnet, 13}
Center plate, 14, 16, 17 mm plate, 1
5,18 ° magnetic air gap, 20,30 ° diaphragm, 21 °
{Flat voice coil, 22, 32} gasket, 2
3a, 23b {input terminal, 25} magnetic fluid, 31}
{Flat short coil, 33} drive coil

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ikuo Shinohara 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation F-term (reference) 5D012 AA03 BA06 BB03 BB04 BB05 FA01 FA02

Claims (2)

[Claims] 1. A U-shaped yoke having one side wall lower in length than the other side wall, and a center plate disposed between one and the other side walls of the U-shaped yoke and sandwiched between first and second magnets. A first plate fixed at one end to an upper end of one side wall of the U-shaped yoke and arranged to form an elongated first magnetic gap between the other end surface and a side surface of the center plate; A second plate provided on the other end of the first plate in parallel with the other side wall; one end fixed to the upper end of the other side wall of the U-shaped yoke; A third plate disposed so as to form an elongated second magnetic gap between the side surface and a third plate fixed at one end side to the third plate via a gasket; And insert it into the magnetic gap Speaker and having a first and a diaphragm is flat voice coil as over a second magnetic gap provided. 2. A U-shaped yoke in which one side wall is lower than the other side wall, and a center plate disposed between one and the other side walls of the U-shaped yoke and held between first and second magnets. A first plate fixed at one end to an upper end of one side wall of the U-shaped yoke and arranged to form an elongated first magnetic gap between the other end surface and a side surface of the center plate; A second plate provided on the other end of the first plate in parallel with the other side wall; one end fixed to the upper end of the other side wall of the U-shaped yoke; A third plate disposed so as to form an elongated second magnetic gap between the side surface and a third plate fixed at one end side to the third plate via a gasket; And insert it into the magnetic gap Speaker and having a diaphragm is flat short coil as over the first and second magnetic gap provided, and wound around a drive coil along the outer circumference of the second plate.