JP2003163992A - Speaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To mount a short ring functioning to suppress the increase of a moderate high frequency impedance in order not to have any influence on the size of a magnetic gap formed between the short ring and an outer ring, or not to generate any impact sound with a voice coil. <P>SOLUTION: This speaker includes magnets 11 and 12; a center plate 13 connected to those magnets 11 and 12; a voice coil 14 disposed so that those magnets 11 and 12 and the outer peripheral face of the center plate 13 can be surrounded, and provided with a coil 14a positioned so as to be faced to the outer peripheral face of the center plate 13; and an outer ring 15 disposed at the outer peripheral side of the voice coil 14, and positioned so as to be faced to the center plate 13. Then, a short ring 16 is circularly mounted on the outer peripheral face of the outer ring 15. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a speaker having a magnetic circuit provided with a short ring.

[0002]

2. Description of the Related Art In order to reduce current distortion caused by an eddy current generated by a current flowing through a voice coil, and suppress an increase in impedance in the middle-high range to improve middle-high range characteristics, a magnetic circuit is made of a nonmagnetic material (gold). , Silver, copper, aluminum, etc.), a speaker equipped with a short ring has been widely used.

FIG. 5 is a partial sectional view schematically showing a first conventional example of a magnetic circuit structure having a short ring attached thereto. The magnetic circuit shown in FIG. 5 is a so-called repulsive magnetic circuit, and includes two disc-shaped or ring-shaped magnets 2
1 and 22 are a disc-shaped center plate 2 made of metal
The magnets 21 and 22 are arranged so that the same poles of the magnets 21 and 22 face each other so as to sandwich 3. A short ring 24 is attached to the outer periphery of the center plate 23.

Further, in FIG. 5, a voice coil 25 is arranged so as to cover the repulsive magnetic circuit. In the voice coil 25, a winding portion 25a around which the coil is wound is arranged at a position facing the center plate 23.
An outer ring 26 having a magnetism collecting function is arranged at a position facing the center plate 23 further on the outer peripheral side of the winding portion 25a of the voice coil 25. A magnetic gap G ′ is formed between the inner peripheral surface of the outer ring 26 and the outer peripheral surface of the center plate 23.

The outer diameters of the magnets 21 and 22 are smaller than the outer diameter of the center plate 23. This is to prevent the voice coil 25 and the magnets 21 and 22 from colliding with each other when the voice coil 25 vibrates.

FIG. 6 is a partial sectional view schematically showing a second conventional example of a magnetic circuit structure having a short ring attached. Similar to FIG. 5, this FIG. 6 is also an example of a repulsive magnetic circuit, but in the case of FIG. 6, the short ring 24 is attached to the outer circumferences of the two magnets 21 and 22, respectively. Since the other structure is the same as that of FIG. 5, the same portions are denoted by the same reference numerals. The outer diameters of the short rings 24 attached to the outer circumferences of the magnets 21 and 22 are substantially the same as the outer diameter of the center plate 23, whereby the outer peripheral surface of the short ring 24 is the outer peripheral surface of the center plate 23. It is almost the same plane.

As in the examples shown in FIGS. 5 and 6,
By mounting the short rings 24 on the respective appropriate parts of the magnetic circuit, the current distortion caused by the eddy current generated by the current flowing through the voice coil 25 is reduced, and the rise of the impedance in the middle and high frequencies is suppressed to suppress the middle and high frequencies. The effect that can be improved can be expected.

[0008]

However, in the magnetic circuit structure of the first conventional example shown in FIG. 5, since the short ring 24 is annularly mounted on the outer peripheral surface of the center plate 23, the winding of the voice coil 25 is wound. In order to secure a predetermined space with the portion 25a, it is necessary to reduce the outer diameter of the center plate 23 by the thickness t of the short ring 24. That is, when the short ring 24 is not attached to the center plate 23, a certain space is secured between the outer peripheral surface of the center plate 23 and the voice coil 25, and a space equivalent to this space is secured. Therefore, the outer diameter of the center plate 23 must be reduced by the thickness t of the short ring 24.

When the outer diameter of the center plate 23 is reduced in this way, the magnetic gap G'formed between the center plate 23 and the outer ring 26 at that time.
Is the original optimum magnetic gap G (center plate 2
3 is larger than the magnetic gap set between the center plate 23 and the outer ring 25 in the case where the short ring 24 is not attached, the magnetic flux density is lowered, and the performance as a speaker is deteriorated. May lead to

Further, in the magnetic circuit structure of the second conventional example shown in FIG. 6, the center plate 23 and the outer ring 26 are used.
The optimum magnetic gap G can be maintained as it is as the magnetic gap formed between the two magnets 21 and 22. However, since the short rings 24 are required for the two magnets 21 and 22, respectively, It is necessary to prepare them, which leads to an increase in component cost and an increase in the assembly process.

Further, by mounting the short rings 24 on the outer peripheral surfaces of the magnets 21 and 22, respectively,
The outer peripheral surface of the short ring 24 is the center plate 2.
Since the outer peripheral surface is substantially flush with the outer peripheral surface of No. 3, when the voice coil 25 vibrates during the operation as a speaker, the voice coil 25 and the short ring 24 are likely to collide with each other, and a noise is generated due to the collision. is there.

The present invention has been made in order to solve the above-mentioned problems, and holds an appropriate magnetic gap and suppresses an increase in impedance in the middle and high frequencies due to the presence of a short ring, whereby the middle and high frequencies are suppressed. It is an object of the present invention to provide a speaker having various advantages such as improved characteristics and prevention of collision between the voice coil and the short ring during operation of the speaker.

[0013]

In order to achieve the above-mentioned object, a speaker of the present invention comprises a magnet and a metal plate which is superposed on and bonded to the magnet.
A voice coil which is arranged so as to surround the magnet and the outer periphery of the metal plate and has a winding portion at a position facing the outer peripheral surface of the metal plate, and on the outer peripheral side of the voice coil and on the metal plate. In a speaker having a magnetic circuit including outer rings arranged at opposing positions, a short ring for short-circuiting an eddy current generated in the magnetic circuit is arranged on the outer peripheral surface of the outer ring.

Further, in the magnetic circuit, the same poles of two magnets are arranged opposite to each other, a metal plate is interposed between the two magnets arranged opposite to each other, and the metal plate faces the outer peripheral surface of the metal plate. A repulsion magnetic circuit having a structure in which a voice coil is arranged at a position where the winding portion is located, and an outer ring is arranged at a position on the outer peripheral side of the voice coil and facing the metal plate. Is preferred.

Further, the short ring mounted on the outer peripheral surface of the outer ring is such that, when the short ring is mounted on the outer peripheral surface of the outer ring, at least one end portion in the vertical direction of the outer peripheral surface of the outer ring is in the vicinity of the end portion. The height dimension of the outer ring is preferably smaller than the height dimension of the outer ring so as to be exposed.

A speaker of another invention is a speaker having a magnetic circuit including a magnet and a magnetism collecting ring arranged so as to face the magnet and have a voice coil therebetween. A short ring that short-circuits the eddy current generated in the magnetic circuit is arranged on the side opposite to the side facing the voice coil.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 is an overall configuration diagram for explaining an embodiment of a speaker of the present invention. In FIG. 1, the magnetic circuit 1 is a repulsive magnetic circuit in this embodiment. That is, the two ring-shaped magnets 11, 1
2 are arranged so that the same poles of the magnets 11 and 12 face each other so as to sandwich the ring-shaped center plate 13 made of metal. And each magnet 11,
A voice coil 14 is arranged on the outer peripheral side of the center plate 13.

On the outer peripheral side of the voice coil 14, an outer ring 15 having a cylindrical magnetism collecting function is provided.
However, the optimum magnetic gap G (see FIG. 2) is provided between the center plate 13 and the outer peripheral surface of the center plate 13. A cylindrical short ring 16 made of a non-magnetic material (copper in this embodiment) is attached to the outer peripheral surface of the outer ring 15.

It should be noted that the inner peripheral surface of the winding portion 14a of the voice coil 14 in which the coil is wound in a cylindrical shape and the outer ring 15 are arranged so as to face the outer peripheral surface of the center plate 13. Further, the outer diameters of the two magnets 11 and 12 are slightly smaller than the outer diameter of the center plate 13, and when these magnets 11 and 12 are joined so as to sandwich the center plate 13, the outer peripheral surface of the center plate 13 is joined. Are projected from the outer peripheral surfaces of the magnets 11 and 12 by a predetermined amount.

In this embodiment, the magnet 1 is attached to the central columnar portion 2b (see FIG. 1) provided at the center of the pedestal 2a.
The center holes of the center plate 13 and the magnet 11 are fitted in this order, and are pressed by the screws 17. However, the magnets 111 and 12 and the center plate 13 may be disc-shaped, and the pedestal 2a may be fixed to the pedestal 2a with an adhesive or the like without providing the central columnar portion 2b.

In the magnetic circuit 1 having such a structure, the portion composed of the magnets 11 and 12 and the center plate 13 is fixed to a pedestal 2a provided in the central portion of a holder 2 having a bottomed cylindrical shape. It At this time, the outer ring 15 is fixed to the inner wall portion of the holder 2, and the voice coil 14 is supported by the inner peripheral side edge of the damper 3 and the inner peripheral side edge of the diaphragm 4 (see FIG. 1).

A frame 5 is attached to the flange portion 2c of the holder 2, the outer peripheral side of the damper 3 is attached to the inner wall surface of the frame 5, and the diaphragm is attached to the opening end. The outer peripheral side of 4 is attached via an edge portion 6.

FIG. 2 is a partial cross-sectional view showing the enlarged right half of the main part of the magnetic circuit 1 used in the speaker shown in FIG. 1 in an enlarged manner. The reference numeral is attached.

As can be seen from FIG. 2, the outer ring 15 has an outer peripheral surface on which a short ring 16 is mounted. Compared with the magnetic circuit structure described as the first conventional example (the structure in which the short ring 24 is attached to the outer peripheral surface of the center plate 23 as shown in FIG. 5), the magnetic circuit structure shown in FIG. In the magnetic circuit 1 shown in FIG. 2, since the outer diameter of the center plate 13 can be maintained as it is, the optimum magnetic gap G between the outer ring 15 and the outer ring 15 can be maintained.

As a result, the effect of suppressing the rise of the impedance in the middle and high frequencies due to the mounting of the short ring 16 is maintained as it is, and it is not necessary to change the outer diameter of the center plate 13. Therefore, the magnetic gap can be optimized. It can be held as it is, and an appropriate magnetic flux density can be obtained.

The magnetic circuit structure of the second conventional example (see FIG. 6).
As shown in FIG. 1), the short ring 16 in the present embodiment is shorter than that of the structure in which the short rings 24 are attached to the outer peripheral surfaces of the magnets 21 and 22, respectively. Since only one is required and the short ring 16 is present on the outer peripheral surface of the outer ring 15, even if the voice coil 14 vibrates, the short ring 16 does not collide with the voice coil 14 and a collision noise can be prevented.

As described above, in this embodiment, the short ring 16 is provided on the outer peripheral surface of the outer ring 15, so that the magnetic gap formed between the center plate 13 and the outer ring 15 is optimally magnetized. It can be held in the gap G. Also, voice coil 1
No collision occurs with the short ring 16 during vibration of No. 4 and no collision noise is generated. In addition, short ring 1
The presence of 6 suppresses an increase in the impedance in the mid-high range due to the eddy current generated by the current flowing through the voice coil 14, thereby improving the mid-high range characteristics.

Further, in the speaker having the repulsive magnetic circuit structure as described above, the short ring 16 is replaced by the outer ring 1.
As described above, the magnetic gap formed between the metal center plate 13 and the outer ring 15 is influenced while making use of the performance of the repulsive magnetic circuit. It is possible to prevent the voice coil 14 and the short ring 16 from colliding with each other when the voice coil 14 vibrates. Moreover, it is possible to sufficiently obtain the effect of suppressing the increase in the impedance in the mid-high range due to the provision of the short ring 16 and thereby improving the mid-high range characteristics, and to further improve the performance as the speaker.

When the outer ring 15 is provided with the short ring 16 on the outer peripheral surface thereof, the outer ring 15
Since the dimension of the short ring 16 in the height direction is made smaller than the dimension of the outer ring 15 in the height direction so that at least one end portion of the outer peripheral surface in the vertical direction is exposed, A step portion A can be formed between the short ring 16 and the short ring 16.

Thus, by providing the step portion B which engages with the step portion A on the holder 2 side to which the outer ring 15 is attached, the outer ring 15 can be easily positioned when it is attached to the holder 2. . Moreover, in that state, the short ring 16 is replaced by the outer ring 15
The outer ring 15 and the short ring 16 can be easily attached to the holder 2 by attaching the outer ring 15 to the holder 2. After the mounting, the step portion A formed between the outer ring 15 and the short ring 16 mounted on the outer ring 15 and the step portion B on the holder 2 side are engaged with each other. It is possible to maintain a stable mounting state without slipping off.

The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the gist of the present invention. For example,
In the above-described embodiment, when the short ring 16 is mounted on the outer peripheral surface of the outer ring 15, the dimension in the height direction is the same as the dimension in the height direction of the outer ring 15, but the invention is not limited to this. Not the short ring 16
May be slightly shorter than the height dimension of the outer ring 15.

FIG. 3 and FIG. 4 show an example thereof, in which the height h1 of the short ring 16 in the height direction is made slightly shorter than the height h2 of the outer ring 15 in the height direction so that the outer circumference of the outer ring 15 can be reduced. This is an example in which the stepped portion A is formed between the outer ring 15 and the short ring 16 by slightly exposing the vicinity of the upper end and the vicinity of the lower end of the surface.

As shown in FIG. 3, a step A is formed due to the difference in the height dimension of the outer ring 15 and the short ring 16, so that the step also on the holder 2 side to which the outer ring 15 is attached. By providing a step portion B (see FIG. 4) that engages with A (in this case, a step portion A formed on the lower end side of the outer ring 15),
When the outer ring 15 is attached to the holder 2 (including the attachment of the short ring 16 to the outer ring 15), the attaching work can be performed easily and reliably.

FIG. 4 shows a state in which the outer ring 15 and the short ring 16 are attached to the holder 2. As an example of a process of making such an attachment, for example, a step in which the outer ring 15 is provided in the holder 2 is shown. It may be fixed to the portion B with an adhesive or the like, and in that state, the short ring 16 may be attached to the outer peripheral surface of the outer ring 15 so as to be annularly mounted. Even when the short ring 16 is attached to the outer ring 15, the short ring 16 is fixed to the outer ring 15 with an adhesive or the like.

In the example of FIG. 3, the size of the short ring 16 is set so that the step A can be formed at each of the upper end and the lower end of the outer ring 15, but the size of the short ring is The size may be such that the step A is formed only on one of the upper end and the lower end of the outer ring 15.

Thus, the dimension of the short ring 16 is set so that the step A can be formed on at least one of the upper end and the lower end of the outer ring 15, and the step B is also provided on the holder 2 side. By forming the outer ring 15, when the outer ring 15 is attached to the holder 2, it is sufficient to position the outer ring 15 on the stepped portion B of the holder 2, so that the positioning can be reliably performed.

In this state, the short ring 16 may be attached so as to be mounted on the outer ring 15, so that the outer ring 15 can be easily attached to the holder 2 and the short ring 16 can be easily attached to the outer ring 15. It can be anything. Further, after the attachment, the step portion A formed between the outer ring 15 and the short ring 16 mounted on the outer ring 15 and the step portion B on the holder 2 side are brought into engagement with each other. It is possible to maintain a stable attached state without slipping.

Further, although the short ring 16 is made of copper in the above-mentioned embodiments, other than copper, for example, gold, silver, aluminum or the like can be used as the member of the short ring 16. Although the short ring 16 has a ring shape, the short ring 16 may be divided into two or three parts, or may be provided so as to contact a part of the outer ring 15 instead of the entire outer circumference. May be.
In this way, the short ring 16 and the outer ring 15
Instead of being attached to the outer circumference of the above, it may be simply arranged in contact. Also, the outer ring 15 is not a complete ring, but a ring-shaped one may be divided into two or three, or may be formed into a substantially ring shape with a gap provided therebetween.

The speaker to which the magnetic circuit 1 is applied is not limited to the one shown in FIG.
Any speaker that uses the outer ring 15 for the magnetic circuit 1 can be widely applied. For example, in the case of a structure in which a ring corresponding to the outer ring 15 is formed inside the voice coil 14 and a magnet is arranged outside the voice coil 14, a short circuit is further provided inside the ring corresponding to the outer ring 15. A ring will be provided.

[0041]

As described above, according to the present invention, the short ring is arranged at a position on the side opposite to the voice coil of the magnetism collecting ring, so that the magnetism collecting ring is It is possible to prevent the magnetic gap formed between them from being affected and to prevent the voice coil and the short ring from colliding with each other when the voice coil vibrates. Moreover, it is possible to sufficiently maintain the effect of suppressing the increase in the impedance in the middle and high frequencies due to the provision of the short ring, and it is possible to further improve the performance as a speaker.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram illustrating an embodiment of a speaker of the present invention.

FIG. 2 is a partial cross-sectional view showing a magnified right half of the magnetic circuit 1 in FIG.

FIG. 3 is a diagram showing a modified example of the magnetic circuit shown in FIG. 2, and is a diagram illustrating an example in which the height dimension of the short ring is made slightly shorter than the height dimension of the outer ring.

FIG. 4 is a diagram showing an example in which the magnetic circuit shown in FIG. 3 is attached to a holder.

FIG. 5 is a diagram illustrating a first conventional example, and is a partial cross-sectional view showing a half of a magnetic circuit taken out and enlarged.

FIG. 6 is a diagram illustrating a second conventional example, and is a partial cross-sectional view showing a half of a magnetic circuit taken out and enlarged.

[Explanation of symbols]

1 magnetic circuit 2 holder 11,12 magnet 13 Center plate 14 voice coils 14a winding part 15 Outer ring (ring for magnetism collection) 16 short ring A, B step G Optimal magnetic gap

Claims (4)

[Claims] 1. A magnet, a metal plate which is superposed on and joined to the magnet, and a position which is arranged so as to surround the outer circumferences of the magnet and the metal plate, and which faces the outer peripheral surface of the metal plate. On the voice coil having a winding part on the outer peripheral side of this voice coil,
In a speaker having a magnetic circuit including an outer ring arranged at a position facing the metal plate, a short ring for short-circuiting an eddy current generated in the magnetic circuit is arranged on an outer peripheral surface of the outer ring. A speaker characterized by that. 2. In the magnetic circuit, the same poles of two magnets are arranged to face each other, the metal plate is interposed between the two magnets arranged to face each other, and an outer peripheral surface of the metal plate. The voice coil is arranged so that the winding portion is located at a position facing to, and the outer ring is arranged at a position facing the metal plate on the outer peripheral side of the voice coil. The speaker according to claim 1, which is a repulsive magnetic circuit having a structure. 3. The short ring disposed on the outer peripheral surface of the outer ring has at least one vertical end of the outer peripheral surface of the outer ring when the short ring is attached to the outer peripheral surface of the outer ring. The speaker according to claim 1 or 2, wherein a dimension in a height direction thereof is smaller than a dimension in a height direction of the outer ring so that a portion near the portion is exposed. 4. A speaker having a magnetic circuit comprising a magnet and a magnetism collecting ring facing the magnet and having a voice coil positioned between the magnet and the speaker, the speaker facing the voice coil of the ring. A speaker characterized in that a short ring for short-circuiting an eddy current generated in the magnetic circuit is arranged on the side opposite to the side.