JP2006211469A - Speaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reliable and small speaker with even a small diameter vibration cone capable of accommodating to a wide reproduction frequency band and enduring large volume input. <P>SOLUTION: The speaker 1 comprises a magnetic circuit 5, a vibration cone 2, a damper 3 and a voice coil 4. The periphery edge of the damper 3 is fixed to an internal periphery plane of a voice coil bobbin 10 forming the voice coil 4. The center of the damper 3 is fixed on the center of the magnetic circuit 5. A through-hole 33 is arranged at the core of the damper 3. The damper 3 is fixed on the magnetic circuit 5 by using the through-hole 33. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a speaker used in various audio devices, and more specifically to a small speaker.

  In order to reduce the size of the acoustic device, it is necessary to reduce the size of the speaker, and it is inevitably desired to reduce the diameter of the diaphragm. However, as the diameter of the diaphragm is reduced, the voice coil is held in the magnetic gap of the magnetic circuit, so the outer diameter of the damper that fixes the inner peripheral end to the outer periphery of the voice coil bobbin must naturally be reduced. . However, if the outer diameter of the damper is reduced as it is, the stiffness of the damper increases, which causes a problem that the lowest resonance frequency of the speaker increases and the reproduction band becomes narrower.

  Therefore, as a measure for solving the above problems, the damper is fixed inside the voice coil bobbin by fixing the outer periphery of the damper to the inner periphery of the voice coil bobbin and the center of the damper to the center of the magnetic circuit. Small speakers that prevent the damper stiffness from becoming large have been put into practical use.

For example, in Japanese Unexamined Patent Application Publication No. 2004-221691 (Patent Document 1),
A dome diaphragm, a voice coil bobbin, a damper, and a magnetic circuit, wherein the dome diaphragm extends from the outer peripheral end of the dome portion along the cylindrical inner surface of the voice coil bobbin; A second fixing portion extending substantially at right angles from an outer peripheral end of the one fixing portion, wherein the damper is disposed inside a space defined by the voice coil bobbin, and an inner peripheral end of the damper is the magnetic circuit A speaker is proposed in which the outer peripheral end of the damper is joined to the outer peripheral end of the dome portion and the cylindrical inner surface of the voice coil bobbin.

In Japanese Patent Laid-Open No. 5-30597 (Patent Document 2), a voice coil is provided with a sleeve formed of a second fixed suspension and a sleeve that is movable in the axial direction of a shaft fixed vertically at the upper end of a center pole of a magnetic circuit. A speaker unit has been proposed in which the length of the contact portion between the voice coil and the shaft of the slider is increased to prevent rolling and thereby preventing disturbance of the sound pressure frequency characteristics.
JP 2004-221691 A (Claims, FIG. 1) JP-A-5-30597 (Claims)

  However, a small speaker with a damper inside a conventional voice coil has a limited area for fixing the damper and the magnetic circuit, and with a small fixed area, the damper and the magnetic circuit are unstablely fixed. The amplitude cannot be held firmly. In addition, due to insufficient fixing between the damper and the magnetic circuit, the vibration system will cause a rolling phenomenon at the time of large input, and the coil will be damaged due to the contact between the magnetic gap and the voice coil, and abnormal noise will be generated. There are challenges.

  For example, Patent Document 1 discloses a speaker structure in which a damper is disposed in a space defined by a voice coil and an inner peripheral end of the damper is fixed to a magnetic circuit in FIG. As shown in FIG. 14, when the bonding area (W1) between the damper 3 and the magnetic circuit 5 is increased, the bonding strength is increased and the rolling phenomenon is eliminated, but the area necessary to function as the damper 3 is decreased, and the damper Therefore, the stiffness of the damper 3 is increased, and the reproduction frequency band may be narrowed.

  On the other hand, as shown in FIG. 15, when the bonding area (W2) between the damper 3 and the magnetic circuit 5 is reduced, the amplitude of the damper 3 can be increased, but the bonding strength is weakened, and the vibration system is reduced as described above. Rolling phenomenon occurs and the reliability for large inputs is poor.

In view of such problems, the present invention provides a small speaker with a small diameter diaphragm, which has a wide reproduction frequency band, can withstand a large input, and has high reliability.

In order to achieve the above object, the invention according to claim 1 of the present invention provides:
The damper is composed of a magnetic circuit, a diaphragm, a damper, and a voice coil. An outer peripheral end of the damper is fixed to an inner peripheral surface of a voice coil bobbin that forms the voice coil, and a center portion of the damper is above a center portion of the magnetic circuit. The speaker is fixed to the
The damper is a speaker in which a through hole is provided at the center thereof, and the damper is fixed on the magnetic circuit using the through hole.

The invention according to claim 2
The speaker according to claim 1,
The damper is
The bottom surface of the center portion is extended downward to form a bottomed cylindrical fixing portion, and a through hole is formed in the center of the bottom surface portion of the fixing portion. The damper is provided in the magnetic circuit. The magnetic circuit is fixed on the center of the magnetic circuit using a holder or a damper holder manufactured separately from the magnetic circuit.

The invention according to claim 3
In the invention of claim 2,
The magnetic circuit is:
A damper holder is provided on the center portion.

The invention according to claim 4
In the invention of claim 3,
The damper holder is
It is a concave part formed on the upper plate which comprises the said magnetic circuit, It is characterized by the above-mentioned.

The invention according to claim 5
In the invention of claim 3,
The damper holder is
It is a through-hole formed on the upper plate which comprises the said magnetic circuit, It is characterized by the above-mentioned.

The invention according to claim 6
In the invention of claim 3,
The damper holder is
It is a ring-shaped protrusion formed on the upper plate constituting the magnetic circuit.

The invention according to claim 7
In the invention of claim 3,
The damper holder is
The ring is a separate ring provided on the upper plate constituting the magnetic circuit.

Further, the invention according to claim 8 is
In the invention of claim 3,
The damper holder is
It is a cup made of a separate synthetic resin provided on the upper plate constituting the magnetic circuit.

The invention according to claim 9 is
In the invention of claim 3,
The damper holder is
It is a cup made of a separate synthetic resin having a protrusion on the inner bottom surface provided on the upper plate constituting the magnetic circuit.

The invention according to claim 10 is
In the invention of claim 3,
The damper holder is
It consists of a bolt, passes through a through hole formed in the damper, and a part of the hole is engaged with the upper plate of the magnetic circuit to hold the damper in the magnetic circuit.

The invention according to claim 11 is
The speaker according to claim 1,
The damper is
A magnetic circuit is formed by a disk-shaped holder main body, a pillar made up of a screw rod provided on the upper surface, and a damper holder made up of a spacer and a nut externally mounted on the pillar. It is fixed to the top.

Further, the invention according to claim 12 is
The speaker according to claim 1,
The damper is
A magnetic circuit is formed by a pillar made of a screw rod engaged with an upper plate constituting the magnetic circuit, and a damper holder made of a spacer and a nut externally mounted on the pillar. It is fixed to the top.

The invention according to claim 13 is
The speaker according to claim 1,
The damper is
A side wall having a through hole in the center, a flat plate, a receiving part for the damper at the upper part, and a base end part made up of a screw rod engaging with the upper plate constituting the magnetic circuit, and a nut It is fixed on a magnetic circuit by a damper holder made of

The invention as set forth in claim 14
The speaker according to claim 1,
The damper is
The side surface having a through hole in the center is a flat plate, the receiving portion of the damper is in the upper portion, and the base end portion is composed of a column made of screw rods that are engaged with the upper plate constituting the magnetic circuit. It is fixed on the magnetic circuit by a damper holder.

The invention according to claim 15 is
The speaker according to claim 1,
The damper is
It is fixed on the magnetic circuit by a damper holder made of a synthetic resin support having a certain area of adhesion with the periphery of the through hole at the top side with a flat plate having a through hole in the center. It is a feature.

The invention according to claim 16
The speaker according to claim 1,
The damper is
It is fixed on the magnetic circuit by a damper holder made of a synthetic resin support column having a flat plate with a through hole in the center and a small-diameter protrusion formed at the tip through a step. It is a feature.

The invention according to claim 17
The speaker according to claim 1,
The damper is
The damper holder is made of a synthetic resin column having a flat plate with a through hole at the center, a small-diameter projection formed at the tip through a step, and a base at the base. It is characterized by being fixed on a circuit.

  The speaker according to the present invention has a through-hole formed in the center of the damper. The damper is produced using the through-hole, or a damper holder directly formed in the magnetic circuit, or separately. It is fixed to the magnetic circuit using a damper holder, and the damper can be firmly fixed to the magnetic circuit. Therefore, even if the voice coil diameter is small, the effective required diameter can be secured so that the stiffness of the damper does not increase, and the size is reduced. It can handle

  In particular, in the present invention, if a bottomed cylindrical fixed portion extending downward is provided on the lower surface and a damper having a through hole formed on the bottom surface is used, the magnetic circuit is provided in the damper holder. Adhesive penetrates into and out of the fixed part, and the damper and magnetic circuit can be bonded and fixed more firmly. The damper holder controls the spread of the adhesive to the surroundings, stabilizing the bonding operation and stabilizing the quality. .

  In addition, by providing a damper holder made of a synthetic resin ring or cup on the upper plate constituting the magnetic circuit, the damper holder can be replaced to accommodate dampers of various diameters. Can be used as a common part for dampers of various diameters, increasing production efficiency.

  Also, when the damper vibrates as the lower gap dimension of the damper vibration part, it needs a size that does not hit the damper, but if a damper holder made of a cup is used, there is no ring equivalent part under the damper vibration part This can be achieved by reducing the outer diameter, and the lower clearance of the damper vibration part can be made larger than when a damper holder made of a ring is used, so that the thickness can be further reduced.

  In addition, as a damper holder that fixes the damper to the magnetic circuit, the damper holder is made of synthetic resin, and the damper is welded and fixed, making it easier to fix the damper than when using an adhesive and increasing work efficiency. Can do.

Moreover, as a damper, a flat plate having a through hole in the center portion is used, and by fixing this damper with a damper holder made of a column, the area of the damper center portion necessary for fixing the damper can be reduced. Even if the voice coil diameter is very small, it can be handled without increasing the stiffness of the damper.
In addition, when the support is used, the damper does not need to have a special shape and may be a flat shape. Therefore, the damper can be easily manufactured and the mold to be used can be easily manufactured.

  In addition, the pillar is passed through a spacer having a through hole in the center, a screw part is provided on the upper part of the pillar, and the damper is fixed to the pillar by clamping the center part of the damper with the spacer and the nut. It becomes easier than when an adhesive is used, and the working efficiency can be increased.

  In addition, the structure in which the support is formed of resin and the center portion of the damper and the support are fixed by welding makes it easier to fix the damper than when an adhesive is used, and the working efficiency can be improved.

  Moreover, the efficiency of fixing work can be improved by fixing a damper and a magnetic circuit with a volt | bolt.

Furthermore, in the present invention, by adopting any one of the above-described various configurations, the damper and the magnetic circuit are firmly fixed without increasing the stiffness of the damper. Even in this case, a wide reproduction frequency band can be obtained, and the occurrence of a rolling phenomenon in the vibration system at the time of large input can be prevented.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a speaker according to the present invention will be specifically described below with reference to the accompanying drawings. Various modifications can be made without departing from the scope of the present invention, and the disclosed embodiments are described below. It is not limited to only. In addition, the same number is attached | subjected to the same part on drawing, description is abbreviate | omitted, and a different point is demonstrated.

As shown in FIG. 1, the speaker 1 of the present invention comprises a vibration system including a dome-shaped diaphragm 2, a damper 3, and a voice coil 4, a frame 9 that supports the vibration system, a pole piece 6, a magnet 7, and a pot yoke 8. And a magnetic circuit 5.
Although the magnetic circuit 5 in the illustrated speaker is an inner magnet type, it can also be applied to an outer magnet type. Therefore, the pole piece 6 will be referred to as an upper plate 6 after a while.

In the speaker 1 having the above-described configuration, the damper 3 is formed integrally with a bottomed cylindrical fixing portion 31 by extending a part of the center portion downward, and a through hole 33 is formed in the bottom surface portion 32 thereof. Therefore, the outer peripheral portion thereof is formed on the inner peripheral surface of the voice coil bobbin 10 around which the voice coil 4 is wound, and the bottom surface portion 32 of the fixing portion 31 is directly or indirectly disposed on the center portion of the upper surface of the upper plate 6. These are each fixed by adhesion.
In addition, all the dampers 3 shown by FIGS. 1-7 are the same forms.

  First, a means for directly bonding and fixing the damper 3 to the center of the upper surface of the upper plate 6 will be described in detail. As shown in FIG. H is formed, and a predetermined amount of the adhesive G is applied in the damper holder H, and the bottom portion 32 of the damper 3 is press-fitted into the damper holder H. The liquid overflows and spreads between the bottom surface portion 32 and the upper plate 6, and a part thereof enters the fixing portion 31 through the through hole 33. Therefore, by hardening the adhesive G in that state, the damper 3 is firmly fixed to the central portion of the upper plate 6 constituting the magnetic circuit 5.

  The form of the damper holder H that also serves as the adhesive reservoir is not limited to the above-mentioned shape. For example, as shown in FIG. 3A, the damper holder H has a required diameter that penetrates the central portion of the upper plate 6. Even a through hole may be a ring-shaped protrusion as shown in FIG.

  Further, as a means for indirectly bonding and fixing the damper 3 to the central portion of the upper surface of the upper plate 6, as shown in FIG. 4, a damper holder 11 made separately can be used.

  As an example of this damper holder 11, as shown in FIG. 4 (a), a through-hole formed in the center of a disc-shaped holder main body 11a made of rubber, resin, metal or the like (the inner diameter is not applicable) The outer diameter of the fixed portion 31 of the damper is approximately equal to the outer diameter of the damper 31). In FIG. 4B, in order to stably provide the holder main body 11a on the upper plate 6, a protruding portion 6a is formed in a ring shape along the outer periphery of the upper plate 6.

  Further, as shown in FIG. 5A, the damper holder 11 is made of the same material as that of the damper holder 111 and has an inner diameter substantially equal to the outer diameter of the bottom face portion 32 of the damper to which the damper holder 11 is not applied. It is good also as a shallow cup shape, and the inner diameter part is good also as the adhesive reservoir h.

  In FIG. 5, the damper holder 11 shown in FIG. 5B is an upper plate for stably providing the cup-shaped damper holder 11 at the center of the upper plate 6 and for positioning the damper holder 11. The damper holder 11 shown in (c) is formed with a protrusion 11b at the center of the back surface of the holder main body 11a, and the center of the top surface of the upper plate 6 is formed. The protrusion 11b is engaged with and held by a concave engaging portion 6b provided in the center, and the center position when the speaker is assembled is determined.

  The damper holder 11 shown in FIG. 6 shows still another form of the damper holder, and this damper holder 11 is made of synthetic resin and has a protrusion 11b on the bottom surface shown in FIG. 5 (c). A columnar protrusion 11c is integrally formed on the inner bottom surface of a cup-shaped holder main body 11a having a shallow bottom. The outer diameter of the protrusion 11c is equal to or slightly smaller than the inner diameter of the through hole formed in the bottom surface portion 32 of the fixing portion 31 of the damper 3 to be applied.

  In the damper holder 11, first, a through hole formed in the bottom surface portion 32 of the fixing portion 31 formed in the damper 3 is fitted into a protruding portion 11c formed to protrude on the inner bottom surface of the damper main body 11a. In a state where the inner bottom surface and the bottom surface portion of the damper 3 are in close contact with each other, the head of the projection 11c is melted by a welding device, and the head is processed so as to have the shape of FIG. And the damper holder 11 are integrated.

  On the other hand, an adhesive is applied to the center portion of the upper surface of the upper plate 6, and the protrusion 11 b on the bottom surface of the damper holder 11 with the damper 3 is inserted into the concave engaging portion 6 c formed on the upper surface of the upper plate 6. Are fitted and fixed together. In addition, the protrusion part 11b of the bottom face of the damper holder 11 is not necessarily an essential component.

  The damper holder shown in FIG. 7 shows still another form. In this damper holder 11, the holder main body 11a is made of a bolt, and the holder main body 11a made of this bolt is formed at the center of the upper plate 6. An engaging screw hole 6c is formed, and the shaft portion of the holder main body 11a is inserted into a through hole provided in the bottom surface portion 32 of the fixing portion 31 of the damper 3, and the shaft portion and the screw hole 6c are engaged. The fixing part 31 is configured to be held on the upper plate 6. At that time, the damper 3 can be more stably fixed on the magnetic circuit 5 by selecting a bolt head having an outer diameter close to the inner diameter of the fixing portion 31 of the damper 3 to which the bolt is applied. .

  The damper holder 21 shown in FIG. 8 includes a disc-shaped holder main body 21a, a column 21b made up of a screw rod having a required length that is suspended from the center of the upper surface of the holder main body 21a, and a cylinder that is externally mounted on the column 21b. A spacer 21c and a nut 21d are formed, and a spacer 21c having a required height and diameter is selected according to the size of a speaker to be obtained and is externally fitted to the column 21b, and the tip of the column 21b is disposed as a damper. 3, the nut 21 d is engaged with the tip end of the support column 21 b to integrate the damper holder 21 and the damper 3. Next, after applying an adhesive into the adhesive holding part 6e formed at the center of the upper surface of the upper plate 6, the holder main body 21a is fitted into the adhesive holding part 6e, and the damper 3 and the damper holder 21 Is fixed on the center of the magnetic circuit 5.

  The damper holder 21 having the above-described configuration does not use the damper 3 having a specific shape as shown in FIGS. 1 to 7, and a flat one, that is, a damper having a flat side surface can be used. In addition to being easy to manufacture, it is also easy to manufacture the mold to be used, and the damper can be stably fixed on the magnetic circuit.

  A damper holder 21 shown in FIG. 9A is used by fitting the damper holder 21 shown in FIG. 8 into an adhesive holding portion 6e formed on the upper plate 6, whereas the upper plate 6 An engaging protrusion 61 is provided at the center of the holder, and an engaging recess formed at the center of the bottom surface of the holder main body 21a is engaged with the protrusion 61 so that the holder main body 21 is adhesively fixed on the upper plate 6. It is a thing.

  Further, in the damper holder 21 shown in FIG. 9 (b), the column 21b provided at the center of the upper surface of the holder main body 21a is inserted from the bottom surface into the through hole 62 provided at the center of the upper plate 6, so that the upper plate A spacer 21c having a required height and diameter is externally mounted on a column 21b projecting from the upper surface of 6, and a damper 3 is mounted. Then, a nut 21d is engaged with the column and the damper 3 is fixed on the upper plate 6.

  A damper holder 21 shown in FIG. 10 is an upper portion of a holder main body 21 a made of a screw rod engaging with a screw of a through hole 62 formed in the center portion of the upper plate 6 as a damper holder 21 that holds the center portion of the damper 3. Further, the receiving portion 21e of the damper 3 is provided so as to be orthogonal to the holder main body 21a. FIG. 10 (a) shows a state in which the center portion of the damper 3 is held by the receiving portion 21e and then the tip of the holder main body 21a. The thing which engaged the nut 21d and integrated the damper 3 and the holder main body 21a is shown. Also. FIG. 10B shows an example in which the damper 3 and the receiving portion 21e are bonded and fixed without using a nut. In either case, a spacer is not used, so that the structure can be simplified. can do.

  The damper holder 21 shown in FIG. 11 is a columnar body having a top surface that can secure an area necessary for reliable bonding with the center portion of the damper 3 as a holder main body 21a. It is possible to position by fitting a recess for engagement provided at the center of the bottom surface of the holder main body 21a into a protrusion formed at the center of the upper surface, as in the embodiment shown in FIG. Since no spacer is used, the structure can be further simplified.

  The damper holder 21 shown in FIG. 12 is formed by integrally forming a projection b having a small diameter via a stepped portion a at the upper end of a cylindrical holder main body 21a made of a synthetic resin having a required diameter. Then, the through hole 32 formed in the center portion of the damper 3 is inserted into the protrusion b to bring the damper 3 and the holder main body 21 into contact with each other, and then the protrusion b is melted so that the damper 3 and the holder main body 21 are brought into contact with each other. When attaching to the speaker, the bottom of the holder column 21a is bonded and fixed to the center of the top surface of the pole piece.

  FIG. 13 shows still another example of the damper holder 21. A projection b having a small diameter is formed on the upper end of a cylindrical holder main body 21a made of synthetic resin having a required diameter via a step a. It is formed integrally, and a mounting base c is integrally formed on the bottom, and a plurality of holes or recesses d are provided on the back surface of the base c, and an adhesive is inserted into the recess d. This structure has a higher adhesive strength.

In this embodiment, the diaphragm of the speaker is illustrated as a dome shape, but the present invention is not limited to the dome shape and can be applied to many types of speakers.

It is sectional drawing which shows an example of the speaker concerning this invention. It is explanatory drawing which shows the process of mounting | wearing the magnetic circuit with the damper of the speaker shown in FIG. It is sectional drawing which shows an example of the upper plate in which the damper holder was formed, Comprising: (a) shows the example which a damper holder consists of a through-hole, (b) shows the example which consists of a ring-shaped protrusion part. It is sectional drawing which shows an example of the damper holder manufactured separately from the magnetic circuit, (a) shows the example which consists of a ring, (b) shows the other example which fixes the said ring to an upper plate. It is sectional drawing which shows another example of the damper holder manufactured separately from the magnetic circuit, (a) is an example of adhering to an upper plate, (b) is another example, (c) is still another An example of It is sectional drawing which shows another example of the damper holder manufactured separately from the magnetic circuit, (a)-(c) shows the attachment process to the upper plate of a damper. It is sectional drawing which shows another example of the damper holder manufactured separately from the magnetic circuit. It is sectional drawing which shows another example of the damper holder manufactured separately from the magnetic circuit. It is explanatory drawing which shows the example of attachment to the upper plate of the damper holder shown in FIG. 8, (a) shows the example which adheres a holder main body on an upper plate, (b) shows the example which adheres to the bottom part of an upper plate. It is sectional drawing which shows another example of a damper holder, (a) shows the example which used the nut for fixation of a damper, (b) shows the example which does not use a nut. It is sectional drawing which shows another example of a damper holder. It is explanatory drawing which shows another example of a damper holder, and its attachment process. The other example of a damper holder is shown, (a) is a front view, (b) is a bottom view. It is explanatory drawing which shows the relationship between the conventional damper and a magnetic circuit. It is another explanatory drawing which shows the relationship between the conventional damper and a magnetic circuit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Speaker 2 Diaphragm 3 Damper 31 Damper fixed part 32 Bottom part of fixed part 33 Through-hole provided in fixed part 4 Voice coil 5 Magnetic circuit 6 Pole piece 7 Magnet 8 Pot yoke 9 Frame 10 Voice coil bobbin 11, 21 Damper holder
H Upper plate damper holder h Adhesive reservoir

Claims (17)

The damper is composed of a magnetic circuit, a diaphragm, a damper, and a voice coil. An outer peripheral end of the damper is fixed to an inner peripheral surface of a voice coil bobbin that forms the voice coil, and a center portion of the damper is on a center portion of the magnetic circuit. In a fixed speaker,
The speaker is characterized in that a through hole is provided in the center of the damper, and the damper is fixed on the magnetic circuit using the through hole. The damper is
The bottom surface of the center portion is extended downward to form a bottomed cylindrical fixed portion, and a through hole is formed in the bottom surface portion of the fixed portion. The damper holder is provided in the magnetic circuit. The speaker according to claim 1, wherein the speaker is fixed on a center portion of the magnetic circuit using a damper holder manufactured separately from the magnetic circuit. The magnetic circuit is:
The speaker according to claim 2, wherein a damper holder is provided on the center portion. The damper holder is
The speaker according to claim 3, wherein the speaker is a concave portion formed on an upper plate constituting the magnetic circuit. The damper holder is
The speaker according to claim 3, wherein the speaker is a through-hole formed on an upper plate constituting the magnetic circuit. The damper holder is
The speaker according to claim 3, wherein the speaker is a ring-shaped protrusion formed on an upper plate constituting the magnetic circuit. The damper holder is
The speaker according to claim 3, wherein the speaker is a separate ring provided on an upper plate constituting the magnetic circuit. The damper holder is
The speaker according to claim 3, wherein the speaker is a cup made of a separate synthetic resin provided on an upper plate constituting the magnetic circuit. The damper holder is
4. The speaker according to claim 3, wherein the speaker is a cup made of a separate synthetic resin provided on an upper plate constituting the magnetic circuit and having a protrusion on an inner bottom surface. The damper holder is
4. It consists of a volt | bolt, penetrates the through-hole formed in the said damper, a part is engaged with the upper plate of the said magnetic circuit, and a damper is hold | maintained to a magnetic circuit, It is characterized by the above-mentioned. The speaker described. The damper is
A magnetic circuit is formed by a disk-shaped holder main body, a pillar made up of a screw rod provided on the upper surface, and a damper holder made up of a spacer and a nut externally mounted on the pillar. The speaker according to claim 1, wherein the speaker is fixed on the top. The damper is
A magnetic circuit is formed by a pillar made of a screw rod engaged with an upper plate constituting the magnetic circuit, and a damper holder made of a spacer and a nut externally mounted on the pillar. The speaker according to claim 1, wherein the speaker is fixed on the top. The damper is
A side wall having a through hole in the center, a flat plate, a receiving part for the damper at the upper part, and a base end part made up of a screw rod engaging with the upper plate constituting the magnetic circuit, and a nut The speaker according to claim 1, wherein the speaker is fixed on a magnetic circuit by a damper holder. The damper is
The side surface having a through hole in the center is a flat plate, the receiving portion of the damper is in the upper portion, and the base end portion is composed of a column made of screw rods that are engaged with the upper plate constituting the magnetic circuit. The speaker according to claim 1, wherein the speaker is fixed on the magnetic circuit by a damper holder. The damper is
It is fixed on the magnetic circuit by a damper holder made of a synthetic resin support having a certain area of adhesion with the periphery of the through hole at the top side with a flat plate having a through hole in the center. The speaker according to claim 1, characterized in that: The damper is
It is fixed on the magnetic circuit by a damper holder made of a synthetic resin support column having a flat plate with a through hole in the center and a small-diameter protrusion formed at the tip through a step. The speaker according to claim 1, characterized in that: The damper is
The damper holder is made of a synthetic resin column having a flat plate with a through hole at the center, a small-diameter projection formed at the tip through a step, and a base at the base. The speaker according to claim 1, wherein the speaker is fixed on a circuit.